189. Davies, SW; Putnam, HM; Ainsworth, T; Baum, JK; Bove, CB; Crosby, SC; Côté, IM; Duplouy, A; Fulweiler, RW; Griffin, AJ; Hanley, TC; Hill, T; Humanes, A; Mangubhai, S; Metaxas, A; Parker, LM; Rivera, HE; Silbiger, NJ; Smith, NS; Spalding, AK; Traylor-Knowles, N; Weigel, BL; Wright, RM; Bates, AE. (2021) Promoting inclusive metrics of success and impact to dismantle a discriminatory reward system in science.PLoS. Biol. 19 Promoting inclusive metrics of success and impact to dismantle a discriminatory reward system in science
Success and impact metrics in science are based on a system that perpetuates sexist and racist "rewards" by prioritizing citations and impact factors. These metrics are flawed and biased against already marginalized groups and fail to accurately capture the breadth of individuals' meaningful scientific impacts. We advocate shifting this outdated value system to advance science through principles of justice, equity, diversity, and inclusion. We outline pathways for a paradigm shift in scientific values based on multidimensional mentorship and promoting mentee well-being. These actions will require collective efforts supported by academic leaders and administrators to drive essential systemic change. DOI PubMed
188. Dunic, JC; Brown, CJ; Connolly, R; Turschwell, MP; Côté, IM. (2021) Long-term declines and recovery of meadow area across the world's seagrass bioregions.Glob. Change Biol. 27: 4096-4109 Long-term declines and recovery of meadow area across the world's seagrass bioregions
attribution; coastal ecosystems; global change; meta-analysis; reconstruction; seagrass; time series
As human impacts increase in coastal regions, there is concern that critical habitats that provide the foundation of entire ecosystems are in decline. Seagrass meadows face growing threats such as poor water quality and coastal development. To determine the status of seagrass meadows over time, we reconstructed time series of meadow area from 175 studies that surveyed 547 sites around the world. We found an overall trajectory of decline in all seven bioregions with a global net loss of 5602 km(2) (19.1% of surveyed meadow area) occurring since 1880. Declines have typically been non-linear, with rapid and historical losses observed in several bioregions. The greatest net losses of area occurred in four bioregions (Tropical Atlantic, Temperate North Atlantic East, Temperate Southern Oceans and Tropical Indo-Pacific), with declining trends being the slowest and most consistent in the latter two bioregions. In some bioregions, trends have recently stabilised or reversed. Losses, however, still outweigh gains. Despite consistent global declines, meadows show high variability in trajectories, within and across bioregions, highlighting the importance of local context. Studies identified 12 different drivers of meadow area change, with coastal development and water quality as the most commonly cited. Overall, however, attributions were primarily descriptive and only 10% of studies used inferential attributions. Although ours is the most comprehensive dataset to date, it still represents only one-tenth of known global seagrass extent, with conspicuous historical and geographic biases in sampling. It therefore remains unclear whether the bioregional patterns of change documented here reflect changes in the world's unmonitored seagrass meadows. The variability in seagrass meadow trajectories, and the attribution of change to numerous drivers, suggest we urgently need to improve understanding of the causes of seagrass meadow loss if we are to improve local-scale management. DOI PubMed
187. Malpica-Cruz, L; Fulton, S; Quintana, A; Zepeda-Dominguez, JA; Quiroga-Garcia, B; Tamayo, L; Noh, JAC; Côté, IM. (2021) Trying to collapse a population for conservation: commercial trade of a marine invasive species by artisanal fishers.Rev. Fish. Biol. Fish. 31: 667-683 Trying to collapse a population for conservation: commercial trade of a marine invasive species by artisanal fishers
Marine invasions; Invasive species management; Lionfish invasion; Artisanal fisheries; Coral reef conservation
Implementing new and effective control strategies to reduce populations of invasive species is needed to offset their negative impacts worldwide. The spread of Indo-Pacific lionfish (Pterois sp.) through much of the western Atlantic has been one of the most publicized marine invasions globally, and is considered a major biodiversity threat whose longer-term impacts are still uncertain. Marine managers have explored several strategies to control lionfish, such as fishing tournaments (derbies) and commercial fisheries. Commercial fisheries for invasive species are controversial because they could create perverse incentives to maintain these populations, and they have never been demonstrated to successfully control target populations. We analyzed the development and impacts of an opportunistic fishing operation aimed at commercializing invasive lionfish in the Mexican Caribbean. We examined official lionfish landings and compared them to catches from lionfish derbies and lionfish densities from locations in the state of Quintana Roo, Mexico. We found that commercial fishers, particularly from one fishing cooperative on Cozumel Island, were effective at catching lionfish, with landings peaking at 20,000 individuals in 2014. This number is comparable to the number of lionfish caught in derbies across the entire Caribbean in the same year. Ecological survey data suggest a similar to 60% reduction in lionfish density on Cozumel reefs over two years (2013-2015), matching the peak landings in the lionfish fishing operation. However, the fishery's apparent success as a control tool during the time window analyzed seemed to trigger its own demise: a decline in landings was followed by evaporating market interest and loss of economic viability. If fisheries are to be established and used as management strategies to control future invasions, managers must develop strategic collaboration plans with commercial fishing partners. DOI
186. McRae, CJ; Huang, WB; Fan, TY; Côté, IM. (2021) Effects of thermal conditioning on the performance of Pocillopora acuta adult coral colonies and their offspring.Coral Reefs 40: 1491-1503 Effects of thermal conditioning on the performance of <i>Pocillopora acuta</i> adult coral colonies and their offspring
Thermal pre-conditioning; Acclimation; Resilience; Climate change; Taiwan
Ocean warming induced by climate change is the greatest threat to the persistence of coral reefs globally. Given the current rate of ocean warming, there may not be sufficient time for natural acclimation or adaptation by corals. This urgency has led to the exploration of active management techniques aimed at enhancing thermal tolerance in corals. Here, we test the capacity for transgenerational acclimation in the reef-building coral <i>Pocillopora acuta</i> as a means of increasing offspring performance in warmer waters. We exposed coral colonies from a reef influenced by intermittent upwelling and constant warm-water effluent from a nuclear power plant to temperatures that matched (26 degrees C) or exceeded (29.5 degrees C) season-specific mean temperatures for three reproductive cycles; offspring were allowed to settle and grow at both temperatures. Heated colonies reproduced significantly earlier in the lunar cycle and produced fewer and smaller planulae. Recruitment was lower at the heated recruitment temperature regardless of parent treatment. Recruit survival did not differ based on parent or recruitment temperature. Recruits from heated parents were smaller and had lower maximum quantum yield (Fv/Fm), a measurement of symbiont photochemical performance. We found no direct evidence that thermal conditioning of adult P. acuta corals improves offspring performance in warmer water; however, chronic exposure of parent colonies to warmer temperatures at the source reef site may have limited transgenerational acclimation capacity. The extent to which coral response to this active management approach might vary across species and sites remains unclear and merits further investigation. DOI PubMed
185. McRae, CJ; Mayfield, AB; Huang, WB; Côté, IM; Fan, TY. (2021) Contrasting Proteomic Responses of Adult and Larval Coral to High Temperatures.Front. Mar. Sci. 8 Contrasting Proteomic Responses of Adult and Larval Coral to High Temperatures
acclimation; climate change; coral; life-stage effects; proteomics
Climate change-induced increases in seawater temperature continue to impact coral reef ecosystems globally. There is a consequent need to characterize the responses of corals to thermal stress to understand the molecular processes underpinning these responses and identify hallmarks of resilience. Here we used an iTRAQ approach to compare the proteomes of adult corals (Pocillopora acuta) that had been thermally conditioned at a control (26 degrees C) or elevated temperature (29.5 degrees C) for three reproductive cycles, as well as the larvae released by these corals. We found that larvae responded more to high-temperature exposure at the protein level than their parents and that different proteins were affected between life stages; a single protein was up-regulated at high temperatures in both adults and their offspring, and its identity is currently unknown. Similarly, different cellular pathways were affected by high-temperature exposure between the coral hosts and their dinoflagellate endosymbionts; proteins involved in translation and protein trafficking were most likely to be affected by high-temperature exposure in the former, with photosynthesis being the most thermo-sensitive process in the latter. Collectively, these findings highlight the importance of considering both life stage and the composition of the coral holobiont when using molecular-scale data to model cellular processes associated with responses to future ocean warming.</p> DOI
184. Murphy, GEP; Dunic, JC; Adamczyk, EM; Bittick, SJ; Côté, IM; Cristiani, J; Geissinger, EA; Gregory, RS; Lotze, HK; O'Connor, MI; Araujo, CAS; Rubidge, EM; Templeman, ND; Wong, MC. (2021) From coast to coast to coast: ecology and management of seagrass ecosystems across Canada.Facets 6: 139-179 From coast to coast to coast: ecology and management of seagrass ecosystems across Canada
eelgrass; Zostera marina; biogeographic regions; habitat structure; phenology; species; communities; human impacts; management; conservation
Seagrass meadows are among the most productive and diverse marine ecosystems, providing essential structure, functions, and services. They are also among the most impacted by human activities and in urgent need of better management and protection. In Canada, eelgrass (Zostera marina) meadows are found along the Atlantic, Pacific, and Arctic coasts, and thus occur across a wide range of biogeographic conditions. Here, we synthesize knowledge of eelgrass ecosystems across Canada's coasts, highlighting commonalities and differences in environmental conditions, plant, habitat, and community structure, as well as current trends and human impacts. Across regions, eelgrass life history, phenology, and general species assemblages are similar. However, distinct regional differences occur in environmental conditions, particularly with water temperature and nutrient availability. There is considerable variation in the types and strengths of human activities among regions. The impacts of coastal development are prevalent in all regions, while other impacts are of concern for specific regions, e.g., nutrient loading in the Atlantic and impacts from the logging industry in the Pacific. In addition, climate change represents a growing threat to eelgrass meadows. We review current management and conservation efforts and discuss the implications of observed differences from coast to coast to coast. DOI
183. Smith, NS; Côté, IM. (2021) Biotic resistance on coral reefs? Direct and indirect effects of native predators and competitors on invasive lionfish.Coral Reefs 40: 1127-1136 Biotic resistance on coral reefs? Direct and indirect effects of native predators and competitors on invasive lionfish
Competition; Consumptive effects; Groupers; Non-consumptive effects; Invasive species control
Biotic resistance is the ability of an ecological community to prevent or limit the establishment or success of non-indigenous species. Native species can confer resistance by outcompeting or directly consuming non-native invaders. The fear of being eaten could also limit invader success, but non-consumptive effects of native predators have rarely been documented as a source of biotic resistance. Here, we test whether native groupers on Caribbean coral reefs can promote biotic resistance to invasive Indo-Pacific lionfish through competition, consumption, and/or through non-consumptive effects. Stomach content analysis of more than 200 groupers, comprising five species, revealed no instances of predation on lionfish. To test for competitive and non-consumptive effects of groupers, we released tagged juvenile lionfish onto reef patches that varied in grouper densities and monitored lionfish behaviours over five weeks. At dawn, during peak grouper and lionfish hunting times, juvenile lionfish hid more on reefs with more grouper predators. Juvenile lionfish were also less active during the day on reefs with high grouper densities. Hiding and inactivity are incompatible with foraging and thus should result in lionfish eating fewer prey and having reduced somatic growth rates. Although there was no substantial effect of interspecific competition on lionfish behaviours, we found that lionfish swam greater distances with increasing densities of intraspecific competitors at dawn. We did not detect a cascading effect of grouper predators on smaller fishes, perhaps because the seasonal peak in prey fish recruitment masked the effects of lower lionfish predation. Fear of native predators by lionfish has the potential to reduce invader foraging success, although it might not fully mitigate the negative effects on native prey communities. Efforts to rebuild grouper populations throughout the Caribbean may still aid in controlling the lionfish invasion despite weak evidence of interspecific competition and lack of direct predation on lionfish, but further research is needed. At broader scales, our findings highlight that the global depletion of large predators can have implications beyond demographic effects on prey. DOI
182. Watkins, HV; Yan, HF; Dunic, JC; Côté, IM. (2021) Research biases create overrepresented "poster children" of marine invasion ecology.Conserv. Lett. 14 Research biases create overrepresented "poster children" of marine invasion ecology
biological invasions; biotic introductions; introduced marine animals; invasion ecology; systematic review; taxonomic bias
Nonnative marine species are increasingly recognized as a threat to the world's oceans, yet are poorly understood relative to their terrestrial and freshwater counterparts. Here, we conducted a systematic review of 2,203 research articles on nonnative marine animals to determine whether the current literature reflects the known diversity of marine invaders, how much we know about these species, and how frequently their impacts are measured. We found that only 39% of nonnative animals listed in the World Register of Introduced Marine Species appeared in the peer-reviewed English literature. Of those, fewer than half were the subject of more than one study. There is currently little focus on the consequences of marine introductions: only 9.9% of studies quantified the impact of nonnative species. Finally, our knowledge of nonnative marine species is heavily limited by strong taxonomic biases consistent across all phyla, resulting in one or two disproportionately well-studied representatives for each phylum, which we refer to as the "poster children" of invasion. These gaps in the literature make it difficult to effectively triage the most detrimental invasive species for management and illustrate the challenges in achieving the global biodiversity goals of preventing and managing the introduction and establishment of invasive species. DOI
181. Berchtold, AE; Côté, IM. (2020) Effect of early exposure to predation on risk perception and survival of fish exposed to a non-native predator.Anim. Behav. 164: 205-216 Effect of early exposure to predation on risk perception and survival of fish exposed to a non-native predator
antipredator behaviour; Indo-Pacific lionfish; invasive predator; predation; prey naivete; risk avoidance
Exposure to predation should affect prey responses to predators by selecting for threat recognition and/or general risk avoidance. We investigated whether native and non-native predator density on the home reefs of juvenile striped parrotfish, Scarus iseri, which reflects their early exposure to predation risk, influences their behavioural responses and survival when faced with some of these predators under controlled conditions. In aquaria, parrotfish exhibited evasive behaviour, in the form of increased immobility and increased distance from threat, in response to visual and chemical cues from native predatory grouper (Epinephelus striatus) but not from invasive Indo-Pacific lionfish (Pterois sp.), suggesting no evidence of risk perception in relation to the non-native predator. However, parrotfish from high-risk reefs exhibited more evasive behaviours and colour responses (i.e. more mottled coloration) in response to all stimuli than parrotfish from low-risk reefs. Moreover, more parrotfish from high-risk reefs than from low-risk reefs survived in direct encounters with lionfish, and those parrotfish that survived were those that had displayed increased immobility when exposed to lionfish cues. We suggest that predation, especially by non-native lionfish, targeting risk-taking fish could result in greater overall cautiousness in some prey populations. This heightened risk avoidance ultimately aids prey fish to evade non-native lionfish, even in the absence of predator recognition. (c) 2020 Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour. DOI
179. Côté, IM; Mills, SC. (2020) Degrees of honesty: cleaning by the redlip cleaner wrasse Labroides rubrolabiatus.Coral Reefs 39: 1693-1701 Degrees of honesty: cleaning by the redlip cleaner wrasse <i>Labroides rubrolabiatus</i>
Cleaning symbiosis; Mutualism; Interspecific interactions; Cleanerfish; Coral reefs
Cleaning symbioses among coral reef fishes are highly variable. Cleanerfishes vary in how much they cooperate with (i.e. remove only ectoparasites) or cheat (i.e. bite healthy tissue, scales or mucus) on their fish clients. As a result, clients use various strategies to enforce cooperation by cleaners (e.g. punishment or partner choice), and cleaners use tactile stimulation to manipulate cheated client behaviour. We provide the first detailed observations of cleaning behaviour of the redlip cleaner wrasse <i>Labroides rubrolabiatus</i> and ask where interactions with this cleanerfish lie on the continuum of cleanerfish honesty, client control, and cleanerfish manipulation. Ninety per cent of redlip cleaner wrasses took jolt-inducing cheating bites from their clients, but they did so at a very low rate (similar to 2 jolts per 100 s inspection). Retaliatory chases by clients were uncommon. Three-quarters (30 of 40) of cleaner wrasses used tactile stimulation on their clients, but rarely did so to reconcile with cheated clients. Instead, the majority (70%) of tactile stimulation events targeted a passing client that then stopped for inspection. The relationship between redlip cleaner wrasses and their clients appears to be less conflictual than those documented in otherLabroidescleanerfishes. Future studies should test whether this low level of conflict is consistent across space and time and is underpinned by a preference for ectoparasites over other client-gleaned items. As an active cleaner that appears to take few cheating bites from their clients,L. rubrolabiatushas the potential to be as important a driver of fish health and community structure on coral reefs as its better-known relatives. DOI
178. Precht, WF; Aronson, RB; Gardner, TA; Gill, JA; Hawkins, JP; Hernandez-Delgado, EA; Jaap, WC; McClanahan, TR; McField, MD; Murdoch, TJT; Nugues, MM; Roberts, CM; Schelten, CK; Watkinson, AR; Côté, IM. (2020) The timing and causality of ecological shifts on Caribbean reefs.Adv. Mar. Biol. 87: 331-360 The timing and causality of ecological shifts on Caribbean reefs
Caribbean reefs have experienced unprecedented changes in the past four decades. Of great concern is the perceived widespread shift from coral to macroalgal dominance and the question of whether it represents a new, stable equilibrium for coral-reef communities. The primary causes of the shift-grazing pressure (top-down), nutrient loading (bottom-up) or direct coral mortality (side-in)-still remain somewhat controversial in the coral-reef literature. We have attempted to tease out the relative importance of each of these causes. Four insights emerge from our analysis of an early regional dataset of information on the benthic composition of Caribbean reefs spanning the years 1977-2001. First, although three-quarters of reef sites have experienced coral declines concomitant with macroalgal increases, fewer than 10% of the more than 200 sites studied were dominated by macroalgae in 2001, by even the most conservative definition of dominance. Using relative dominance as the threshold, a total of 49 coral-to-macroalgae shifts were detected. This total represents similar to 35% of all sites that were dominated by coral at the start of their monitoring periods. Four shifts (8.2%) occurred because of coral loss with no change in macroalgal cover, 15 (30.6%) occurred because of macroalgal gain without coral loss, and 30 (61.2%) occurred owing to concomitant coral decline and macroalgal increase. Second, the timing of shifts at the regional scale is most consistent with the side-in model of reef degradation, which invokes coral mortality as a precursor to macroalgal takeover, because more shifts occurred after regional coral-mortality events than expected by chance. Third, instantaneous observations taken at the start and end of the time-series for individual sites showed these reefs existed along a continuum of coral and macroalgal cover. The continuous, broadly negative relationship between coral and macroalgal cover suggests that in some cases coral-to-macroalgae phase shifts may be reversed by removing sources of perturbation or restoring critical components such as the herbivorous sea urchin Diadema antillarum to the system. The five instances in which macroalgal dominance was reversed corroborate the conclusion that macroalgal dominance is not a stable, alternative community state as has been commonly assumed. Fourth, the fact that the loss in regional coral cover and concomitant changes to the benthic community are related to punctuated, discrete events with known causes (i.e. coral disease and bleaching), lends credence to the hypothesis that coral reefs of the Caribbean have been under assault from climate-change-related maladies since the 1970s. DOI PubMed
177. Bates, AE; Cooke, RSC; Duncan, MI; Edgar, GJ; Bruno, JF; Benedetti-Cecchi, L; Côté, IM; Lefcheck, JS; Costello, MJ; Barrett, N; Bird, TJ; Fenberg, PB; Stuart-Smith, RD. (2019) Climate resilience in marine protected areas and the 'Protection Paradox'.Biol. Conserv. 236: 305-314 Climate resilience in marine protected areas and the 'Protection Paradox'
Restricting human activities through Marine Protected Areas (MPAs) is assumed to create more resilient biological communities with a greater capacity to resist and recover following climate events. Here we review the evidence linking protection from local pressures (e.g., fishing and habitat destruction) with increased resilience. Despite strong theoretical underpinnings, studies have only rarely attributed resilience responses to the recovery of food webs and habitats, and increases in the diversity of communities and populations. When detected, resistance to ocean warming and recovery after extreme events in MPAs have small effect sizes against a backdrop of natural variability. By contrast, large die-offs are well described from MPAs following climate stress events. This may be in part because protection from one set of pressures or drivers (such as fishing) can select for species that are highly sensitive to others (such as warming), creating a 'Protection Paradox'. Given that climate change is overwhelming the resilience capacity of marine ecosystems, the only primary solution is to reduce carbon emissions. High quality monitoring data in both space and time can also identify emergent resilience signals that do exist, in combination with adequate reference data to quantify the initial system state. This knowledge will allow networks of diverse protected areas to incorporate spatial refugia against climate change, and identify resilient biological components of natural systems. Sufficient spatial replication further offers insurance against losses in any given MPA, and the possibility for many weak signals of resilience to accumulate. DOI
176. Bose, APH; Zayonc, D; Avrantinis, N; Ficzycz, N; Fischer-Rush, J; Francis, FT; Gray, S; Manning, F; Robb, H; Schmidt, C; Spice, C; Umedaly, A; Warden, J; Côté, IM. (2019) Effects of handling and short-term captivity: a multi-behaviour approach using red sea urchins, Mesocentrotus franciscanus.PeerJ 7 Effects of handling and short-term captivity: a multi-behaviour approach using red sea urchins, <i>Mesocentrotus franciscanus</i>
Invertebrate; Reintroduction; Relocation; Echinoderm; Stress; Animal welfare
Understanding the effects of captivity-induced stress on wild-caught animals after their release back into the wild is critical for the long-term success of relocation and reintroduction programs. To date, most of the research on captivity stress has focused on vertebrates, with far less attention paid to invertebrates. Here, we examine the effect of short-term captivity (i.e., up to four days) on self-righting, aggregation, and predator-escape behaviours in wild-caught red sea urchins, <i>Mesocentrotus franciscanus</i> , after their release back into the wild. Aggregation behaviour, which has been linked to feeding in sea urchins, was not affected by handling or captivity. In contrast, the sea urchins that had been handled and released immediately, as well as those that were handled and held captive, took longer to right themselves and were poorer at fleeing from predators than wild, unhandled sea urchins. These results indicate that handling rather than captivity impaired these behaviours in the short term. The duration of captivity did not influence the sea urchin behaviours examined. Longer-term monitoring is needed to establish what the fitness consequences of these short-term behavioural changes might be. Our study nevertheless highlights the importance of considering a suite of responses when examining the effects of capture and captivity. Our findings, which are based on a locally abundant species, can inform translocation efforts aimed at bolstering populations of ecologically similar but depleted invertebrate species to retain or restore important ecosystem functions. DOI PubMed
175. Brandl, SJ; Morais, RA; Casey, JM; Parravicini, V; Tornabene, L; Goatley, CHR; Côté, IM; Baldwin, CC; Schiettekatte, NMD; Bellwood, DR. (2019) Response to Comment on "Demographic dynamics of the smallest marine vertebrates fuel coral reef ecosystem functioning".Science 366 Response to Comment on "Demographic dynamics of the smallest marine vertebrates fuel coral reef ecosystem functioning"
Allgeier and Cline suggest that our model overestimates the contributions of cryptobenthic fishes to coral reef functioning. However, their 20-year model ignores the basic biological limits of population growth. If incorporated, cryptobenthic contributions to consumed fish biomass remain high (20 to 70%). Disturbance cycles and uncertainties surrounding the fate of large fishes on decadal scales further demonstrate the important role of cryptobenthic fishes. DOI PubMed
174. Brandl, SJ; Rasher, DB; Côté, IM; Casey, JM; Darling, ES; Lefchecku, JS; Duffy, JE. (2019) Coral reef ecosystem functioning: eight core processes and the role of biodiversity.Front. Ecol. Environ. 17: 445-453 Coral reef ecosystem functioning: eight core processes and the role of biodiversity
Coral reefs are in global decline. Reversing this trend is a primary management objective but doing so depends on understanding what keeps reefs in desirable states (ie "functional"). Although there is evidence that coral reefs thrive under certain conditions (eg moderate water temperatures, limited fishing pressure), the dynamic processes that promote ecosystem functioning and its internal drivers (ie community structure) are poorly defined and explored. Specifically, despite decades of research suggesting a positive relationship between biodiversity and ecosystem functioning across biomes, few studies have explored this relationship in coral reef systems. We propose a practical definition of coral reef functioning, centered on eight complementary ecological processes: calcium carbonate production and bioerosion, primary production and herbivory, secondary production and predation, and nutrient uptake and release. Connecting research on species niches, functional diversity of communities, and rates of the eight key processes can provide a novel, quantitative understanding of reef functioning and its dependence on coral reef communities that will chart the transition of coral reefs in the Anthropocene. This will contribute urgently needed guidance for the management of these important ecosystems. DOI
173. Brandl, SJ; Tornabene, L; Goatley, CHR; Casey, JM; Morais, RA; Côté, IM; Baldwin, CC; Parravicini, V; Schiettekatte, NMD; Bellwood, DR. (2019) Demographic dynamics of the smallest marine vertebrates fuel coral reef ecosystem functioning.Science 364: 1189 Demographic dynamics of the smallest marine vertebrates fuel coral reef ecosystem functioning
How coral reefs survive as oases of life in low-productivity oceans has puzzled scientists for centuries. The answer may lie in internal nutrient cycling and/or input from the pelagic zone. Integrating meta-analysis, field data, and population modeling, we show that the ocean's smallest vertebrates, cryptobenthic reef fishes, promote internal reef fish biomass production through extensive larval supply from the pelagic environment. Specifically, cryptobenthics account for two-thirds of reef fish larvae in the near-reef pelagic zone despite limited adult reproductive outputs. This overwhelming abundance of cryptobenthic larvae fuels reef trophodynamics via rapid growth and extreme mortality, producing almost 60% of consumed reef fish biomass. Although cryptobenthics are often overlooked, their distinctive demographic dynamics may make them a cornerstone of ecosystem functioning on modern coral reefs. DOI PubMed
172. Bruno, JF; Côté, IM; Toth, LT. (2019) Climate Change, Coral Loss, and the Curious Case of the Parrotfish Paradigm: Why Don't Marine Protected Areas Improve Reef Resilience?Annual Review of Marine Science 11 Climate Change, Coral Loss, and the Curious Case of the Parrotfish Paradigm: Why Don't Marine Protected Areas Improve Reef Resilience?
coral reef; disturbance; parrotfish; resilience; resistance; climate change
Scientists have advocated for local interventions, such as creating marine protected areas and implementing fishery restrictions, as ways to mitigate local stressors to limit the effects of climate change on reef-building corals. However, in a literature review, we find little empirical support for the notion of managed resilience. We outline some reasons for why marine protected areas and the protection of herbivorous fish (especially parrotfish) have had little effect on coral resilience. One key explanation is that the impacts of local stressors (e.g., pollution and fishing) are often swamped by the much greater effect of ocean warming on corals. Another is the sheer complexity (including numerous context dependencies) of the five cascading links assumed by the managed-resilience hypothesis. If reefs cannot be saved by local actions alone, then it is time to face reef degradation head-on, by directly addressing anthropogenic climate change-the root cause of global coral decline. DOI PubMed
171. Francis, FT; Filbee-Dexter, K; Yan, HF; Côté, IM. (2019) Invertebrate herbivores: Overlooked allies in the recovery of degraded coral reefs?Glob. Ecol. Conserv. 17 Invertebrate herbivores: Overlooked allies in the recovery of degraded coral reefs?
Coral-algal phase shift; Coral reef degradation; Maguimithrax spinosissimus; Invertebrate grazing; Macroalgae; Regime shifts; Tripneustes ventricosus
A key question for coral reef conservation is whether reefs dominated by macroalgae can recover. Since the near-disappearance of the herbivorous urchin Diadema antillarum in the Caribbean, a prevalent management paradigm has focused on protecting herbivorous fishes to trigger shifts back to a coral-rich state. However, in the absence of D. antillarum, the contribution of other large macroinvertebrates to herbivory intensity has been largely overlooked. We used day and night field surveys and behavioural observations at 16 degraded reef patches in the Bahamas to measure the abundance of large herbivorous macroinvertebrates and their consumption of fleshy macroalgae. Tripneustes sea urchins and Maguimithrax crabs were the main herbivorous macroinvertebrates on our sites and were active mainly at night, with 97% of urchins and 45% of crabs observed consuming fleshy macroalgae. By comparison, < 5% of herbivorous fishes observed ate macroalgae. In the laboratory, Tripneustes sea urchins and Maguimithrax crabs readily consumed macroalgae (at rates of 0.19 g h(-1) and 0.38 g h(-1), respectively), but their low abundance on patch reefs (4 crabs and 2.3 urchins per reef, on average) translated into low overall rates of macroalgal removal. Perhaps for this reason, there was no relationship between the density of these large macroinvertebrates or their grazing rate and macroalgal cover on patch reefs. Nevertheless, we calculated that macroalgal consumption by Maguimithrax crabs alone could exceed macroalgae production with a doubling of their current low abundance; a 2.6-fold increase in Tripneustes urchin abundance would achieve the same result. Our results suggest that large herbivorous macroinvertebrates, some of which are currently the target of artisanal fishing in many Caribbean countries, could contribute greatly to the recovery of coral reefs with established macroalgal communities, at least in patch reef habitats. (C) 2019 Published by Elsevier B.V. DOI
170. Francis, FT; Howard, BR; Berchtold, AE; Branch, TA; Chaves, LCT; Dunic, MC; Favaro, B; Jeffrey, KM; Malpica-Cruz, L; Maslowski, N; Schultz, JA; Smith, NS; Côté, IM. (2019) Shifting headlines? Size trends of newsworthy fishes.PeerJ 7 Shifting headlines? Size trends of newsworthy fishes
Fisheries; Sportfishing; Charismatic megafauna; Journalism; Shifting baseline; Record-setting
The shifting baseline syndrome describes a gradual lowering of human cognitive baselines, as each generation accepts a lower standard of resource abundance or size as the new norm. There is strong empirical evidence of declining trends of abundance and body sizes of marine fish species reported from docks and markets. We asked whether these widespread trends in shrinking marine fish are detectable in popular English-language media, or whether news writers, like many marine stakeholders, are captive to shifting baselines. We collected 266 English-language news articles, printed between 1869 and 2015, which featured headlines that used a superlative adjective, such as 'giant', 'huge', or 'monster', to describe an individual fish caught. We combined the reported sizes of the captured fish with information on maximum species-specific recorded sizes to reconstruct trends of relative size (reported size divided by maximum size) of newsworthy fishes over time. We found some evidence of a shifting baseline syndrome in news media over the last 140 years: overall, the relative length of the largest fish worthy of a headline has declined over time. This pattern held for charismatic fish species (e.g. basking sharks, whale sharks, giant mantas), which are now reported in the media at smaller relative lengths than they were near the turn of the 20th century, and for the largest species under high risk of extinction. In contrast, there was no similar trend for pelagic gamefish and oceanic sharks, or for species under lower risk of extinction. While landing any individual of the large-bodied 'megafish' may be newsworthy in part because of their large size relative to other fish species, the 'megafish' covered in our dataset were small relative to their own species-on average only 56% of the species-specific maximum length. The continued use in the English-language media of superlatives to describe fish that are now a fraction of the maximum size they could reach, or a fraction of the size they used to be, does reflect a shifting baseline for some species. Given that media outlets are a powerful tool for shaping public perception and awareness of environmental issues, there is a real concern that such stories might be interpreted as meaning that superlatively large fish still abound. DOI PubMed
169. Haines, LJ; Côté, IM. (2019) Homing decisions reveal lack of risk perception by Caribbean damselfish of invasive lionfish.Biol. Invasions 21: 1657-1668 Homing decisions reveal lack of risk perception by Caribbean damselfish of invasive lionfish
Prey naivete; Pterois sp; Predation risk; Movement ecology; Marine invasions
Prey naivete, or the failure of prey to recognize non-native predators due to a lack of co-evolutionary history, is thought to underpin the large impact of invasive Indo-Pacific lionfish (Pterois sp.) on coral reef fish populations in the western Atlantic. Most previous studies of lionfish recognition have taken place in experimental tanks that did not mimic natural conditions or used bottle or cage field designs that constrained natural behaviour. To alleviate these issues, we compared the homing patterns of experimentally translocated Caribbean bicolor damselfish (Stegastes partitus) in the presence and absence of standardized models of a lionfish, of an ecologically similar native piscivore (black grouper; Mycteroperca bonaci), and of a native non-piscivore (French grunt, Haemulon flavolineatum) in the field. The native grouper model elicited a strong predator avoidance response: translocated damselfish became unlikely to home when released beyond 2m from their territory and took longer to do so. In contrast, damselfish facing a lionfish model exhibited similar homing behaviours to those of damselfish in the presence of a non-piscivorous grunt and in the absence of any model. Fish length and translocation distance also influenced homing: damselfish stopped homing when released more than 5.6m away from their territory and larger individuals crossed wider sand gaps. Overall, our findings are consistent with the idea that bicolor damselfish are naive to the threat of predation presented by lionfish, but also with the notion that damselfish might be assessing, but deeming to be low, the threat of a stalking predator hunting over open sand. Both mechanisms point to inaccurate risk perception in relation to invasive lionfish. More broadly, we highlight a novel experimental translocation approach to evaluate behavioural responses of native prey species to novel predators under realistic field conditions. DOI
168. Howard, BR; Francis, FT; Côté, IM; Therriault, TW. (2019) Habitat alteration by invasive European green crab (Carcinus maenas) causes eelgrass loss in British Columbia, Canada.Biol. Invasions 21: 3607-3618 Habitat alteration by invasive European green crab (Carcinus maenas) causes eelgrass loss in British Columbia, Canada
Habitat alteration; Aquatic conservation; Disturbance; Ecosystem engineering; Enclosure; Zostera marina
Dominant, habitat-forming plant species, such as seagrasses, are key components of coastal ecosystems worldwide. Multiple stressors, including invasive species that directly alter, remove, or replace the foundation plant species, threaten these ecosystems. On the Atlantic coast of North America, ecosystem engineering by invasive European green crab (Carcinus maenas) has been linked to the loss of some eelgrass (Zostera marina) beds. However, the interaction of the same co-occurring species on the Pacific coast has not been investigated. We conducted an enclosure experiment in Barkley Sound, British Columbia, to determine if the engineering impacts of green crabs on Pacific eelgrass ecosystems mirror those previously identified on the Atlantic coast. Eelgrass shoot density declined rapidly over 4 weeks, with a 73-81% greater loss in enclosures with high crab density compared to the low-density and control treatments. The low ratio of eelgrass blades to rhizomes in the high-density treatment suggests that blade shredding, rather than bioturbation of whole plants, was the main mechanism of eelgrass loss. Eelgrass was detected in green crab stomach contents, consistent with observations from the Atlantic coast. Crab density did not have a detectable effect on the biomass or community composition of benthic fauna associated with eelgrass over the duration of the experiment. The eelgrass loss we observed was consistent with losses observed on the Atlantic coast, which raises management concerns on the Pacific coast, particularly in areas where green crabs co-occur with other coastal stressors and with ecologically and economically important species such as salmon. DOI
167. Malpica-Cruz, L; Green, SJ; Côté, IM. (2019) Temporal and ontogenetic changes in the trophic signature of an invasive marine predator.Hydrobiologia 839: 71-86 Temporal and ontogenetic changes in the trophic signature of an invasive marine predator
Lionfish; Marine invasions; Stable isotope ecology; Trophic ecology
Many successful invasive species have generalist diets, but the extent to which they can track changing resources has seldom been documented. Stable isotope analysis was used to measure dietary shifts with ontogeny and over time in relation to changes in prey availability for Indo-Pacific lionfish (Pterois sp.). These are invasive predators that are well established throughout the western North Atlantic and Caribbean where they have caused significant decreases in native reef fish populations in some areas. Samples and observations were made off New Providence Island, Bahamas during the summers of 2008 and 2010. Lionfish delta N-15 and delta C-13 values increased only weakly with body length, suggesting that processes other than growth also contribute to stable isotope variability. The trophic niche of lionfish changed significantly between years, concomitant with large changes in native fish prey abundance and community structure. The trophic niche of large lionfish expanded, increasing in trophic diversity at the population level and showing lower individual trophic similarity, while that of small lionfish remained similar in size but shifted towards more N-15-enriched and C-13-depleted prey sources. The ability of lionfish to modify their diet over time may have facilitated their expansion and persistence at high densities in some areas despite local prey depletion. DOI
166. Smith, NS; Côté, IM. (2019) Multiple drivers of contrasting diversity-invasibility relationships at fine spatial grains.Ecology 100 Multiple drivers of contrasting diversity-invasibility relationships at fine spatial grains
biotic resistance; diversity-invasibility hypothesis; invasibility metrics; invasion paradox; invasion susceptibility; meta-analysis; spatial scale; systematic review
The diversity-invasibility hypothesis and ecological theory predict that high-diversity communities should be less easily invaded than species-poor communities, but empirical evidence does not consistently support this prediction. While fine-scale experiments tend to yield the predicted negative association between diversity and invasibility, broad-scale observational surveys generally report a positive correlation. This conflicting pattern between experiments and observational studies is referred to as the invasion paradox and is thought to arise because different processes control species composition at different spatial scales. Here, we test empirically the extent to which the strength and direction of published diversity-invasibility relationships depend on spatial scale and on the metrics used to measure invasibility. Using a meta-analytic framework, we explicitly separate the two components of spatial scale: grain and extent, by focusing on fine-grain studies that vary in extent. We find evidence of multiple drivers of the paradox. When we consider only fine-grain studies, we still observe conflicting patterns between experiments and observational studies. In contrast, when we examine studies that are conducted at both a fine grain and fine extent, there is broad overlap in effect sizes between experiments and observation, suggesting that comparing studies with similar extents resolves the paradox at local scales. However, we uncover systematic differences in the metrics used to measure invasibility between experiments, which use predominantly invader performance, and observational studies, which use mainly invader richness. When we consider studies with the same metric (i.e., invader performance), the contrasting associations between study types also disappear. It is not possible, at present, to fully disentangle the effect of spatial extent and metric on the paradox because both variables are systematically associated in different directions with study type. There is therefore an urgent need to conduct experiments and observational studies that incorporate the full range of variability in spatial extent and invasibility metric. DOI PubMed
165. Tamburello, N; Ma, BO; Côté, IM. (2019) From individual movement behaviour to landscape-scale invasion dynamics and management: a case study of lionfish metapopulations.Philos. Trans. R. Soc. B-Biol. Sci. 374 From individual movement behaviour to landscape-scale invasion dynamics and management: a case study of lionfish metapopulations
lionfish; invasive species; behaviour; movement; metapopulation
Modelling the dynamics of small, interconnected populations, or metapopulations, can help pinpoint habitat patches that are critical for population persistence in patchy habitats. For conservation purposes, these patches are typically earmarked for protection, but for invasive species management, these patches could be targeted to hasten the populations' demise. Here, we show how metapopulation modelling, coupled with an understanding of size-dependent dispersal behaviour, can be used to help optimize the distribution of limited resources for culling specific populations of invasive Indo-Pacific lionfish (Pterois volitans) in the western Atlantic. Through simulation using fitted model parameters, we derive three insights that can inform management. First, culling lionfish from target patches reduces the probability of lionfish occupancy at surrounding patches. Second, this effect depends on patch size and connectivity, but is strongest at the local scale and decays with distance. Finally, size-dependent dispersal in lionfish means that size-selective culling can change both a population's size distribution and dispersal potential, with cascading effects on network connectivity, population dynamics and management outcomes. By explicitly considering seascape structure and movement behaviour when allocating effort to the management of invasive species, managers can optimize resource use to improve management outcomes. This article is part of the theme issue 'Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation'. DOI PubMed
164. Côté, IM; Smith, NS. (2018) The lionfish Pterois sp invasion: Has the worst-case scenario come to pass?J. Fish Biol. 92 The lionfish Pterois sp invasion: Has the worst-case scenario come to pass?
biotic invasion; biotic resistance; coral reefs; environmental management; invasive species control; Scorpaenidae
This review revisits the traits thought to have contributed to the success of Indo-Pacific lionfish Pterois sp. as an invader in the western Atlantic Ocean and the worst-case scenario about their potential ecological effects in light of the more than 150 studies conducted in the past 5years. Fast somatic growth, resistance to parasites, effective anti-predator defences and an ability to circumvent predator recognition mechanisms by prey have probably contributed to rapid population increases of lionfish in the invaded range. However, evidence that lionfish are strong competitors is still ambiguous, in part because demonstrating competition is challenging. Geographic spread has likely been facilitated by the remarkable capacity of lionfish for prolonged fasting in combination with other broad physiological tolerances. Lionfish have had a large detrimental effect on native reef-fish populations in the northern part of the invaded range, but similar effects have yet to be seen in the southern Caribbean. Most other envisaged direct and indirect consequences of lionfish predation and competition, even those that might have been expected to occur rapidly, such as shifts in benthic composition, have yet to be realized. Lionfish populations in some of the first areas invaded have started to decline, perhaps as a result of resource depletion or ongoing fishing and culling, so there is hope that these areas have already experienced the worst of the invasion. In closing, we place lionfish in a broader context and argue that it can serve as a new model to test some fundamental questions in invasion ecology. DOI PubMed
162. Francis, FT; Côté, IM. (2018) Fish movement drives spatial and temporal patterns of nutrient provisioning on coral reef patches.Ecosphere 9 Fish movement drives spatial and temporal patterns of nutrient provisioning on coral reef patches
consumer-mediated nutrients; cross-ecosystem subsidies; diel movement; fish excretion; nitrogen supply; nutrient budgets
Nutrient provisioning by animals can be a major driver of primary productivity in ecosystems. Animal-mediated nutrient sources are particularly important in nutrient-poor systems such as coral reefs. However, aggregations of mobile animals might lead to temporal and spatial variability in local nutrient availability, which is not well understood. In this study, we quantified how patterns of fish movement and abundance influence the stability of nitrogen provisioning on Bahamian coral reefs. We empirically measured and modeled nitrogen excretion estimates for 16 coral reef fish communities and combined these measurements with fish abundance and behavioral observations to compare reef nutrient budgets on diel, monthly, and annual time scales. Diel reef nitrogen provisioning by fishes varied greatly, with diurnal rates being on average four times greater than nocturnal rates. Diurnal rates were highly variable among reefs and were driven primarily by migratory grunts (Haemulidae) resting over reefs during the day but foraging off reefs at night. At the reef scale, overall nitrogen excretion rates were correlated with grunt abundance; however, grunt abundance could not be predicted by any reef physical characteristics. Within-reef grunt excretion rates changed little across a 4-month period but varied significantly over two years, indicating that nutrient supply on a patch reef is not stable over long periods of time. Quantifying how nutrient provisioning on patch reefs is linked to fish activity and movement patterns and how provisioning varies on different spatial and temporal scales is important for understanding overall patterns of primary productivity on reefs. DOI
161. Gordon, TAC; Harding, HR; Clever, FK; Davidson, IK; Davison, W; Montgomery, DW; Weatherhead, RC; Windsor, FM; Armstrong, JD; Bardonnet, A; Bergman, E; Britton, JR; Côté, IM; D'agostino, D; Greenberg, LA; Harborne, AR; Kahilainen, KK; Metcalfe, NB; Mills, SC; Milner, NJ; Mittermayer, FH; Montorio, L; Nedelec, SL; Prokkola, JM; Rutterford, LA; Salvanes, AGV; Simpson, SD; Vainikka, A; Pinnegar, JK; Santos, EM. (2018) Fishes in a changing world: learning from the past to promote sustainability of fish populations.J. Fish Biol. 92 Fishes in a changing world: learning from the past to promote sustainability of fish populations
challenges; fish; fisheries; future; global change; sustainability
Populations of fishes provide valuable services for billions of people, but face diverse and interacting threats that jeopardize their sustainability. Human population growth and intensifying resource use for food, water, energy and goods are compromising fish populations through a variety of mechanisms, including overfishing, habitat degradation and declines in water quality. The important challenges raised by these issues have been recognized and have led to considerable advances over past decades in managing and mitigating threats to fishes worldwide. In this review, we identify the major threats faced by fish populations alongside recent advances that are helping to address these issues. There are very significant efforts worldwide directed towards ensuring a sustainable future for the world's fishes and fisheries and those who rely on them. Although considerable challenges remain, by drawing attention to successful mitigation of threats to fish and fisheries we hope to provide the encouragement and direction that will allow these challenges to be overcome in the future. DOI PubMed
160. Howard, BR; Barrios-O'Neill, D; Alexander, ME; Dick, JTA; Therriault, TW; Robinson, TB; Côté, IM. (2018) Functional responses of a cosmopolitan invader demonstrate intraspecific variability in consumer-resource dynamics.PeerJ 6 Functional responses of a cosmopolitan invader demonstrate intraspecific variability in consumer-resource dynamics
Biological invasion; Carcinus maenas; Morphology; European green crab; Prediction; Prey handling; Risk assessment
Background. Variability in the ecological impacts of invasive species across their geographical ranges may decrease the accuracy of risk assessments. Comparative functional response analysis can be used to estimate invasive consumer-resource dynamics, explain impact variability, and thus potentially inform impact predictions. The European green crab (Carcinus maenas) has been introduced on multiple continents beyond its native range, although its ecological impacts appear to vary among populations and regions. Our aim was to test whether consumer-resource dynamics under standardized conditions are similarly variable across the current geographic distribution of green crab, and to identify correlated morphological features. Methods. Crabs were collected from multiple populations within both native (Northern Ireland) and invasive regions (South Africa and Canada). Their functional responses to local mussels (Mytilus spp.) were tested. Attack rates and handling times were compared among green crab populations within each region, and among regions (Pacific Canada, Atlantic Canada, South Africa, and Northern Ireland). The effect of predator and prey morphology on prey consumption was investigated. Results. Across regions, green crabs consumed prey according to a Type II (hyperbolic) functional response curve. Attack rates (i.e., the rate at which a predator finds and attacks prey), handling times and maximum feeding rates differed among regions. There was a trend toward higher attack rates in invasive than in native populations. Green crabs from Canada had lower handling times and thus higher maximum feeding rates than those from South Africa and Northern Ireland. Canadian and Northern Ireland crabs had significantly larger claws than South African crabs. Claw size was a more important predictor of the proportion of mussels killed than prey shell strength. Discussion. The differences in functional response between regions reflect observed impacts of green crabs in the wild. This suggests that an understanding of consumer- resource dynamics (e.g., the per capita measure of predation), derived from simple, standardized experiments, might yield useful predictions of invader impacts across geographical ranges. DOI PubMed
159. D'Aloia, CC; Daigle, RM; Côté, IM; Curtis, JMR; Guichard, F; Fortin, MJ. (2017) A multiple-species framework for integrating movement processes across life stages into the design of marine protected areas.Biol. Conserv. 216: 93-100 A multiple-species framework for integrating movement processes across life stages into the design of marine protected areas
Pelagic larval duration; Home range; Marxan; MPA; Movement; Larval dispersal
A major objective of marine protected area (MPA) network design is to ensure the persistence of species with diverse life histories and functional traits. Considering how species differ in their propensity to move within and between MPAs is therefore a key consideration for multi-species MPA network design. Here, we propose a conceptual framework to incorporate ecological processes that affect movement at multiple life stages into the MPA network design process. We illustrate how our framework can be implemented using a set of hypothetical species that represent regional trait diversity in coastal British Columbia, Canada. We focused on two ecological processes: (1) dispersal during the larval phase and (2) daily home range movement during the adult phase. To identify functional connectivity patterns, we used a biophysical model to simulate larval dispersal, and then prioritized highly-connected patches using a reserve selection algorithm. To ensure that individual reserves were commensurate with home ranges, we also imposed reserve size constraints. Candidate areas for protection were identified based on multi-species connectivity patterns and home range size constraints. Collectively, this conceptual framework offers a flexible approach to multi-species, cross-life stage conservation planning, which can be further adapted to address complex life histories. As marine conservation efforts around the globe aim to design ecologically connected networks of protected areas, the integration of movement and connectivity data throughout ontogeny will be a key component of effective multi-species MPA network design. DOI
158. Daigle, RM; Archambault, P; Halpern, BS; Lowndes, JSS; Côté, IM. (2017) Incorporating public priorities in the Ocean Health Index: Canada as a case study.PLoS One 12 Incorporating public priorities in the Ocean Health Index: Canada as a case study
The Ocean Health Index (OHI) is a framework to assess ocean health by considering many benefits (called 'goals') provided by the ocean provides to humans, such as food provision, tourism opportunities, and coastal protection. The OHI framework can be used to assess marine areas at global or regional scales, but how various OHI goals should be weighted to reflect priorities at those scales remains unclear. In this study, we adapted the framework in two ways for application to Canada as a case study. First, we customized the OHI goals to create a national Canadian Ocean Health Index (COHI). In particular, we altered the list of iconic species assessed, added methane clathrates and subsea permafrost as carbon storage habitats, and developed a new goal, 'Aboriginal Needs', to measure access of Aboriginal people to traditional marine hunting and fishing grounds. Second, we evaluated various goal weighting schemes based on preferences elicited from the general public in online surveys. We quantified these public preferences in three ways: using Likert scores, simple ranks from a best-worst choice experiment, and model coefficients from the analysis of elicited choice experiment. The latter provided the clearest statistical discrimination among goals, and we recommend their use because they can more accurately reflect both public opinion and the trade-offs faced by policy-makers. This initial iteration of the COHI can be used as a baseline against which future COHI scores can be compared, and could potentially be used as a management tool to prioritise actions on a national scale and predict public support for these actions given that the goal weights are based on public priorities. DOI
157. Eger, AM; Curtis, JMR; Fortin, MJ; Côté, IM; Guichard, F. (2017) Transferability and scalability of species distribution models: a test with sedentary marine invertebrates.Canadian Journal of Fisheries and Aquatic Sciences 74: 766-778 Transferability and scalability of species distribution models: a test with sedentary marine invertebrates
We found the predictive accuracy of species distribution models (SDMs) for sedentary marine invertebrates to be dependent on the methodology of their application. We explored three applications of SDMs: first a model tested at a scale smaller than at which it was trained (downscaled), second a model tested at scale larger than its training scale (upscaled), and third a model tested at the same scale but outside the extent for which it was trained (transferred). The accuracies of these models were compared with the "reference" models that were trained and tested at the same scale and extent. We found that downscaled SDMs had higher predictive accuracy than reference SDMs. Transferred and upscaled models had lower predictive accuracy than their reference counterparts but still performed better than random, making them potentially acceptable alternatives where information is lacking for imminent decisions or in cost-restricted scenarios. Our results provide insights into the techniques available for researchers and managers developing SDMs at varying scales, with different species, and with different levels of initial information. DOI
156. Howard, BR; Therriault, TW; Côté, IM. (2017) Contrasting ecological impacts of native and non-native marine crabs: a global meta-analysis.Mar. Ecol.-Prog. Ser. 577: 93-103 Contrasting ecological impacts of native and non-native marine crabs: a global meta-analysis
Aquatic invasive species; Marine crustaceans; Meta-analysis; Ecological impact; Taxonomic distinctiveness hypothesis
Concern about the impacts of invasive species on invaded communities is often linked to the expectation that invasive consumers will be more effective at using resources than native ones. Many invasive marine crabs (infraorder Brachyura) are regarded as particularly capable consumers; however, native crabs can also exert significant influence on community structure. We used marine crabs as a focal group to test whether non-native consumers have greater impacts than native consumers on native prey populations by conducting a systematic review and meta-analysis of 834 crab foraging experiments. In addition to the effect of crab origin (non-native or native) on prey abundance, we examined the effects of interaction type (direct or indirect), prey type, and experimental design. Overall, direct consumption by non-native crabs did not reduce prey abundance more than predation by native crabs, although the magnitude of reductions in prey abundance varied with prey type and experimental design. Indirect inter actions with crabs (i. e. through trophic cascades with crabs as the initiators) generally increased the abundance of native species. The direct and indirect impacts of non-native crabs were significantly greater than those of native crabs on primary producers and in simplified experiments with low species diversity. Thus, detecting differences between native and non-native crabs may be heavily influenced by experimental design. Importantly, we found few studies that considered direct interactions (competitive or predatory) between native and non-native crabs. These inter actions should be a focus of future research because they could greatly alter consumption rates and overall prey mortality in the wild. DOI
155. Jeffrey, KM; Côté, IM; Irvine, JR; Reynolds, JD. (2017) Changes in body size of Canadian Pacific salmon over six decades.Canadian Journal of Fisheries and Aquatic Sciences 74: 191-201 Changes in body size of Canadian Pacific salmon over six decades
Body size can sometimes change rapidly as an evolutionary response to selection or as a phenotypic response to changes in environmental conditions. Here, we revisit a classic case of rapid change in body size of five species of Pacific salmon (Oncorhynchus spp.) caught in Canadian waters, with a six-decade analysis (1951-2012). Declines in size at maturity of up to 3 kg in Chinook (Oncorhynchus tshawytscha) and 1 kg in coho salmon (Oncorhynchus kisutch) during the 1950s and 1960s were later reversed to match or exceed earlier sizes. In contrast, there has been little change in sockeye salmon (Oncorhynchus nerka) sizes and initial declines in pink (Oncorhynchus gorbuscha) and chum salmon (Oncorhynchus keta) sizes have halted. Biomass of competing salmon species contributed to changes in size of all five species, and ocean conditions, as reflected by the North Pacific Gyre Oscillation and the Multivariate ENSO (El Nino -Southern Oscillation) indices, explained variation in four of the species. While we have identified a role of climate and density dependence in driving salmon body size, any additional influence of fisheries remains unclear. DOI
154. Malpica-Cruz, L; Haider, W; Smith, NS; Fernandez-Lozada, S; Côté, IM. (2017) Heterogeneous Attitudes of Tourists toward Lionfish in the Mexican Caribbean: Implications for Invasive Species Management.Front. Mar. Sci. 4 Heterogeneous Attitudes of Tourists toward Lionfish in the Mexican Caribbean: Implications for Invasive Species Management
coral reef conservation; stated preference choice experiments; invasive species management; marine tourism management; latent-class analysis
Indo-Pacific lionfish (Pterois volitans and P miles) are invasive predators established throughout the Wider Caribbean. They have already caused significant ecological impacts and have the potential to affect local economies that depend on coral reefs. Snorkeling and scuba diving are important activities that rely on esthetically pleasant reefs. We asked whether lionfish-invaded reefs have lower esthetic value and whether fees to help control the invasion might be acceptable to recreational divers and snorkelers in the Mexican Caribbean. To do so, we conducted a choice experiment in which tourists were asked to indicate their preferences for coral reef images with varying attributes that can be affected by lionfish. We specified a priori two classes of respondents, i.e., snorkelers and divers, but two latent classes of recreational divers (casual vs. committed) emerged on the basis of their preferences. Tourist age, commitment to snorkeling/diving, and lionfish awareness explained class membership. Casual divers and snorkelers preferred reefs with lionfish and accepted their impacts on the reefs. In contrast, committed divers disliked lionfish and associated impacts, and would elect to dive elsewhere if such impacts were high. Casual divers and snorkelers preferred options with low lionfish control fees, while committed divers were willing to pay high fees. Our results indicate potential economic impacts of the lionfish invasion in regions that depend on reef-related tourism, and that lionfish control fees might be acceptable to some but not all recreational users. However, because all tourists favored to a greater extent reef features that can be affected detrimentally by lionfish than they favored lionfish themselves, we predict that managing the lionfish invasion should be beneficial to the local reef tourism industry. DOI
153. Nanninga, GB; Côté, IM; Beldade, R; Mills, SC. (2017) Behavioural acclimation to cameras and observers in coral reef fishes.Ethology 123: 705-711 Behavioural acclimation to cameras and observers in coral reef fishes
acclimation; anemonefish; beaugregory; changepoint analysis; in situ observations; observer effect
Observer presence can bias behavioural studies of animals in both the wild and the laboratory. Despite existing evidence for significant observer effects across several taxa, little is known about the minimum periods of acclimation that should precede behavioural observations. To date, most studies either do not report any acclimation periods or include a non-specific period without empirically quantifying its appropriateness. Here, we conducted in situ behavioural observations of two species of demersal coral reef fishes using cameras and/or observers to examine the biases associated with either approach. For both treatments, we generated 25min time series of a number of vigilance-associated behaviours (i.e., distance from shelter and mate, time out of shelter, swimming activity) and estimated the point of acclimation using changepoint analysis. In the camera trials, acclimation in both species appeared to occur between 2 and 7min for different behaviours. When an observer was present, however, no apparent acclimation occurred until the observer left the area. Overall, our findings demonstrate that (i) behavioural studies of wild fishes conducted by an observer may be biased due to permanent observer effects, and (ii) when using video equipment, a species- and behaviour-specific acclimation period should precede behavioural scoring. DOI
152. Nedelec, SL; Mills, SC; Radford, AN; Beldade, R; Simpson, SD; Nedelec, B; Côté, IM. (2017) Motorboat noise disrupts cooperative interspecific interactions.Sci Rep 7 Motorboat noise disrupts cooperative interspecific interactions
Human-made noise is contributing increasingly to ocean soundscapes. Its physical, physiological and behavioural effects on marine organisms are potentially widespread, but our understanding remains largely limited to intraspecific impacts. Here, we examine how motorboats affect an interspecific cleaning mutualism critical for coral reef fish health, abundance and diversity. We conducted in situ observations of cleaning interactions between bluestreak cleaner wrasses (Labroides dimidiatus) and their fish clients before, during and after repeated, standardised approaches with motorboats. Cleaners inspected clients for longer and were significantly less cooperative during exposure to boat noise, and while motorboat disturbance appeared to have little effect on client behaviour, as evidenced by consistency of visit rates, clientele composition, and use of cleaning incitation signals, clients did not retaliate as expected (i.e., by chasing) in response to increased cheating by cleaners. Our results are consistent with the idea of cognitive impairments due to distraction by both parties. Alternatively, cleaners might be taking advantage of distracted clients to reduce their service quality. To more fully understand the importance of these findings for conservation and management, further studies should elucidate whether the efficacy of ectoparasite removal by cleaners is affected and explore the potential for habituation to boat noise in busy areas. DOI
151. Smith, NS; Côté, IM; Martinez-Estevez, L; Hind-Ozan, EJ; Quiros, AL; Johnson, N; Green, SJ; Cornick, L; Shiffman, D; Malpica-Cruz, L; Besch, AG; Shiel-Rolle, N. (2017) Diversity and Inclusion in Conservation: A Proposal for a Marine Diversity Network.Front. Mar. Sci. 4 Diversity and Inclusion in Conservation: A Proposal for a Marine Diversity Network
barriers to inclusion; diversity in science; marine conservation; online communities; online network
Low diversity among scientists and practitioners is rampant in conservation. Currently, conservation professionals do not reflect the same diversity of perspectives and experiences of the world as the communities who bear the largest burden for Implementing-or adverse consequences for failing to implement conservation action. Acknowledging and describing the problem is important. But policies and programmes must also be put in place to correct it. Here, we highlight some measurable benefits of workforce diversity, and give an overview of some of the barriers to inclusion in marine conservation that help perpetuate low workforce diversity. Importantly, we underscore actions that both individuals and groups can take to alleviate such barriers. In particular, we describe the establishment of an online Marine Diversity Network, which conference participants proposed during a focus group meeting at the 4th International Marine Conservation Congress. The network will serve to bring together people from across the globe, from a variety of backgrounds, and from all career stages, to share knowledge, experiences and ideas, to provide and receive mentorship in marine conservation, and to forge new collaborations. Removing barriers to diverse participation requires coordinated, mindful actions by individuals and organizations. We hope that the proposed network and other actions presented in this paper find widespread support, and that they might serve both as inspiration and guide to other groups concerned with increasing diversity and inclusivity. DOI
150. Smith, NS; Green, SJ; Akins, JL; Miller, S; Côté, IM. (2017) Density-dependent colonization and natural disturbance limit the effectiveness of invasive lionfish culling efforts.Biol. Invasions 19: 2385-2399 Density-dependent colonization and natural disturbance limit the effectiveness of invasive lionfish culling efforts
Coral reef fish; Hurricanes; Invasive predators; Invasive species control
Culling can be an effective management tool for reducing populations of invasive species to levels that minimize ecological effects. However, culling is labour-intensive, costly, and may have unintended ecological consequences. In the Caribbean, culling is widely used to control invasive Indo-Pacific lionfish, Pterois volitans and P. miles, but the effectiveness of infrequent culling in terms of reducing lionfish abundance and halting native prey decline is unclear. In a 21-month-long field experiment on natural reefs, we found that culling effectiveness changed after the passage of a hurricane part-way through the experiment. Before the hurricane, infrequent culling resulted in substantial reductions in lionfish density (60-79%, on average, albeit with large uncertainty) and slight increases in native prey species richness, but was insufficient to stem the decline in native prey biomass. Culling every 3 months (i.e., quarterly) and every 6 months (i.e., biannually) had similar effects on lionfish density and native prey fishes because of high rates of lionfish colonization among reefs. After the hurricane, lionfish densities were greater on all culled reefs compared to non-culled reefs, and prey biomass declined by 92%, and species richness by 71%, on biannually culled reefs. The two culling frequencies we examined therefore seem to offer a poor trade-off between the demonstrated conservation gains that can be achieved with frequent culling and the economy of time and money realized by infrequent culling. Moreover, stochastic events such as hurricanes can drastically limit the effectiveness of culling efforts. DOI
149. Sutherland, WJ; Barnard, P; Broad, S; Clout, M; Connor, B; Côté, IM; Dicks, LV; Doran, H; Entwistle, AC; Fleishman, E; Fox, M; Gaston, KJ; Gibbons, DW; Jiang, Z; Keim, B; Lickorish, FA; Markillie, P; Monk, KA; Pearce-Higgins, JW; Peck, LS; Pretty, J; Spalding, MD; Tonneijck, FH; Wintle, BC; Ockendon, N. (2017) A 2017 Horizon Scan of Emerging Issues for Global Conservation and Biological Diversity.Trends in Ecology & Evolution 32: 31-40 A 2017 Horizon Scan of Emerging Issues for Global Conservation and Biological Diversity
We present the results of our eighth annual horizon scan of emerging issues likely to affect global biological diversity, the environment, and conservation efforts in the future. The potential effects of these novel issues might not yet be fully recognized or understood by the global conservation community, and the issues can be regarded as both opportunities and risks. A diverse international team with collective expertise in horizon scanning, science communication, and conservation research, practice, and policy reviewed 100 potential issues and identified 15 that qualified as emerging, with potential substantial global effects. These issues include new developments in energy storage and fuel production, sand extraction, potential solutions to combat coral bleaching and invasive marine species, and blockchain technology. DOI
148. Begin, C; Schelten, CK; Nugues, MM; Hawkins, J; Roberts, C; Côté, IM. (2016) Effects of Protection and Sediment Stress on Coral Reefs in Saint Lucia.PLoS One 11 Effects of Protection and Sediment Stress on Coral Reefs in Saint Lucia
The extent to which Marine Protected Areas (MPAs) benefit corals is contentious. On one hand, MPAs could enhance coral growth and survival through increases in herbivory within their borders; on the other, they are unlikely to prevent disturbances, such as terrestrial runoff, that originate outside their boundaries. We examined the effect of spatial protection and terrestrial sediment on the benthic composition of coral reefs in Saint Lucia. In 2011 (10 to 16 years after MPAs were created), we resurveyed 21 reefs that had been surveyed in 2001 and analyzed current benthic assemblages as well as changes in benthic cover over that decade in relation to protection status, terrestrial sediment influence (measured as the proportion of terrigenous material in reef-associated sediment) and depth. The cover of all benthic biotic components has changed significantly over the decade, including a decline in coral and increase in macroalgae. Protection status was not a significant predictor of either current benthic composition or changes in composition, but current cover and change in cover of several components were related to terrigenous content of sediment deposited recently. Sites with a higher proportion of terrigenous sediment had lower current coral cover, higher macroalgal cover and greater coral declines. Our results suggest that terrestrial sediment is an important factor in the recent degradation of coral reefs in Saint Lucia and that the current MPA network should be complemented by measures to reduce runoff from land. DOI
147. Chaves, LCT; Hall, J; Feitosa, JLL; Côté, IM. (2016) Photo-identification as a simple tool for studying invasive lionfish Pterois volitans populations.Journal of Fish Biology 88: 800-804 Photo-identification as a simple tool for studying invasive lionfish Pterois volitans populations
capture-mark-recapture studies; citizen science; I3S Pattern; photo-tagging
Photo-tagging, i.e. using a specific software to match colour patterns on photographs, was tested as a means to identify individual Indo-Pacific Pterois volitans to assist with population and movement studies of this invasive species. The stripe pattern on the flank of adult P. volitans (n = 48) was the most individually distinctive of three body regions tested, leading to correct individual identification on 68 and 82% of tests with a single and two images of the reference individual, respectively. Photo-tagging is inexpensive, logistically simple and can involve citizen scientists, making it a viable alternative to traditional tagging to provide information on P. volitans distribution, movement patterns and recolonization rates after removals. DOI
146. Côté, IM; Darling, ES; Brown, CJ. (2016) Interactions among ecosystem stressors and their importance in conservation.Proceedings of the Royal Society B-Biological Sciences 283 Interactions among ecosystem stressors and their importance in conservation
ecological surprises; non-additive effects; global change; ecological experiments
Interactions between multiple ecosystem stressors are expected to jeopardize biological processes, functions and biodiversity. The scientific community has declared stressor interactions-notably synergies-a key issue for conservation and management. Here, we review ecological literature over the past four decades to evaluate trends in the reporting of ecological interactions (synergies, antagonisms and additive effects) and highlight the implications and importance to conservation. Despite increasing popularity, and ever-finer terminologies, we find that synergies are (still) not the most prevalent type of interaction, and that conservation practitioners need to appreciate and manage for all interaction outcomes, including antagonistic and additive effects. However, it will not be possible to identify the effect of every interaction on every organism's physiology and every ecosystem function because the number of stressors, and their potential interactions, are growing rapidly. Predicting the type of interactions may be possible in the near-future, using meta-analyses, conservation-oriented experiments and adaptive monitoring. Pending a general framework for predicting interactions, conservation management should enact interventions that are robust to uncertainty in interaction type and that continue to bolster biological resilience in a stressful world. DOI
145. Côté, IM; Favaro, C. (2016) The scientific value of scientific whaling.Marine Policy 74: 88-90 The scientific value of scientific whaling
Cetacean management; Commercial whaling; International Convention for Regulation of Whaling; Research output
Scientific whaling has polarized opinion for decades, and its scientific value has been intensely debated. Here, the output of scientific whaling programs is examined by comparing it to the scientific output pertaining to whales of countries that do not practice scientific whaling. Between 1986 and 2013, whaling and non-whaling countries produced, on average, similar total numbers of publications that were directly relevant to the goals of the scientific whaling permits issued by the International Whaling Commission (IWC), and similar numbers of papers that were relevant to whale ecology and conservation but not directly related to IWC goals. Half of the scientific productivity of scientific whaling countries resulted from non-lethal data collection. One-third of publications by whaling countries were published in peer-reviewed outlets, compared to twice as many for non whaling countries. Publications by whaling countries were cited 4 times less often than those of non-whaling countries, with no evidence of citation discrimination against whaling countries since the citation rates of papers that did and did not use lethal sampling were similar. These academic criteria suggest that although the overall volume of science produced by scientific whaling countries is similar to that of non-whaling countries, the quality of the science is not. Arguably, academic criteria are not the best way to assess the usefulness of science for management and conservation, but demonstrating links between the science produced by scientific whaling, its integration in management plans and actions, and shifts towards sustainable exploitation or recovery of whale populations is challenging. DOI
144. Daigle, RM; Haider, W; Fernandez-Lozada, S; Irwin, K; Archambault, P; Côté, IM. (2016) From coast to coast: Public perception of ocean-derived benefits in Canada.Marine Policy 74: 77-84 From coast to coast: Public perception of ocean-derived benefits in Canada
Best-worst scaling; Discrete choice experiment; Marine conservation; Ocean health; Public opinion; Policy-making
The ocean provides many benefits, such as food provision, tourism opportunities, and coastal protection, to people around the world. To manage ocean uses in a sustainable way, managers need to limit some activities, but which benefits are most important to preserve? To answer this question, an opinion survey of 2000 Canadians was conducted, combining a best-worst scaling experiment and a Likert-scale choice instrument, to determine their perception of 10 ocean-derived benefits. Both approaches showed that 'Clean Waters' is highly important across all Canadians. The importance of other benefits such as 'Food Provision' and 'Biodiversity' varied with respondent age, political affiliation, and/or seafood-eating frequency. A majority (83%) of Canadians favoured non-extractive over extractive benefits. This case study demonstrates how survey approaches can reveal the values and preferences of the general public and provide an inclusive means to help managers align environmental policies with public priorities. (C) 2016 Elsevier Ltd. All rights reserved. DOI
143. Malpica-Cruz, L; Chaves, LCT; Côté, IM. (2016) Managing marine invasive species through public participation: Lionfish derbies as a case study.Marine Policy 74: 158-164 Managing marine invasive species through public participation: Lionfish derbies as a case study
Coral reefs; Fishing tournaments; Invasive species management; Marine invasions
The management of invasive species can be facilitated by public participation. The drivers of public involvement and success at invasive removal in tournaments (derbies) to catch Indo-Pacific lionfish (Pterois volitans/miles) in the Western Atlantic were examined. Information on 69 lionfish derbies held in the wider Caribbean region from 2010 to 2015 was compiled. Derbies attended mainly by artisanal fishers reported lower catches but higher participation" than derbies dominated by recreational divers or attended by a mixed public. As predicted, the number of lionfish caught increased with effort and with time since lionfish were established in an area. In contrast, participation was best predicted by national wealth (GDP per capita) and number of local dive shops. From the point of view of public engagement, derbies should therefore be held in areas where lionfish are well established, and where the pool of potential participants is large. However, if-the management goal is instead to slow the invasion, early detection is critical. The focus should then shift to areas where no or very few lionfish have been detected, and the derby approach modified to a more frequent or continuous, monitoring-like incentive scheme. DOI
142. Schultz, JA; Cloutier, RN; Côté, IM. (2016) Evidence for a trophic cascade on rocky reefs following sea star mass mortality in British Columbia.PeerJ 4 Evidence for a trophic cascade on rocky reefs following sea star mass mortality in British Columbia
Marine diseases; Starfish; Community shifts; Mass mortality; Environmental change; Sea star wasting syndrome; Echinoderm population
Echinoderm population collapses, driven by thsease outbreaks and climatic events, may be important drivers of population dynamics, ecological shifts and biodiversity. The northeast Pacific recently experienced a mass mortality of sea stars. In Howe Sound, British Columbia, the sunflower star Pycnopodia helianthoides a previously abundant predator of bottom -dwelling invertebrates began to show signs of a wasting syndrome in early September 2013, and dense aggregations disappeared from many sites in a matter of weeks. Here, we assess changes in subtidal community composffion by comparing the abundance of fish, invertebrates and macroalgae at 20 sites in Howe Sound before and after the 2013 sea star mortality to evaluate evidence for a trophic cascade. We observed changes in the abundance of several species after the sea star mortality, most notably a four -fold increase in the number ofgreen sea urchins, Strongylocentrotus droebachiensis, and a significant decline in kelp cover, which are together consistent with a trophic cascade. Qualitative data on the abundance of sunflower stars green urchins from a citizen science database show that the patterns of echinodermabundance detected at our study sites reflected wider local trends. The trophic cascade evident at the scale of Howe Sound was observed athalf of the study sites. It remains unclear whether the urchin response was triggered directly, via a reduction in urchin mortality, or indirectly, via a shift in urchin distribution into areas previously occupied by the predatory sea stars. Understanding the ecological implications of sudden and extreme population declines may further elucidate the role of echinoderms in temperate seas, and provide insight into the resilience of marine ecosystems to biological disturbances. DOI
141. Alvarez-Filip, L; Paddack, MJ; Ben Collen; Robertson, DR; Côté, IM. (2015) Simplification of Caribbean Reef-Fish Assemblages over Decades of Coral Reef Degradation.PLoS One 10 Simplification of Caribbean Reef-Fish Assemblages over Decades of Coral Reef Degradation
Caribbean coral reefs are becoming structurally simpler, largely due to human impacts. The consequences of this trend for reef-associated communities are currently unclear, but expected to be profound. Here, we assess whether changes in fish assemblages have been non-random over several decades of declining reef structure. More specifically, we predicted that species that depend exclusively on coral reef habitat (i.e., habitat specialists) should be at a disadvantage compared to those that use a broader array of habitats (i.e., habitat generalists). Analysing 3727 abundance trends of 161 Caribbean reef-fishes, surveyed between 1980 and 2006, we found that the trends of habitat-generalists and habitat-specialists differed markedly. The abundance of specialists started to decline in the mid-1980s, reaching a low of similar to 60% of the 1980 baseline by the mid-1990s. Both the average and the variation in abundance of specialists have increased since the early 2000s, although the average is still well below the baseline level of 1980. This modest recovery occurred despite no clear evidence of a regional recovery in coral reef habitat quality in the Caribbean during the 2000s. In contrast, the abundance of generalist fishes remained relatively stable over the same three decades. Few specialist species are fished, thus their population declines are most likely linked to habitat degradation. These results mirror the observed trends of replacement of specialists by generalists, observed in terrestrial taxa across the globe. A significant challenge that arises from our findings is now to investigate if, and how, such community-level changes in fish populations affect ecosystem function. DOI PubMed
140. Beldade, R; Mills, SC; Claudet, J; Côté, IM. (2015) More coral, more fish? Contrasting snapshots from a remote Pacific atoll.PeerJ 3 More coral, more fish? Contrasting snapshots from a remote Pacific atoll
Coral cover; Coral-fish relationship; Fish assemblages; Fish community structure; Functional relationship; Resilience
Coral reefs are in decline across the globe as a result of overexploitation, pollution, disease and, more recently, climate change. The impacts of changes in coral cover on associated fish communities can be difficult to predict because of the uneven dependence of reef fish species on corals for food, shelter or the three-dimensional structure they provide. We compared live coral cover, reef fish community metrics, and their associations in two surveys of the lagoon of the remote atoll of Mataiva (French Polynesia) carried out 31 years apart. In contrast to the general pattern of decreasing coral cover reported for many parts of the Indo-Pacific region, live coral cover increased 6-7 fold at Mataiva between 1981 and 2012, and fish density nearly doubled. The stable overall reef fish species richness belied a significant shift in community structure. There was little overlap in community composition across years, and fish assemblages in 2012 were more homogeneous in composition than they were in 1981. Changes in species abundance were not clearly related to species-specific reliance on corals. The strong positive relationships between live coral cover and fish diversity and abundance noted in 1981, when coral cover rarely exceeded 10%, were no longer present in 2012, when coral cover rarely fell below this value. The most parsimonious explanation for these contrasting relationships is that, over the combined range of coral cover observed in the 1981 and 2012 snapshots, there is a rapidly asymptotic relationship between coral and fish. Our results, and other data from the south and west Pacific, suggest that fish diversity and abundance might accumulate rapidly up to a threshold of approximately 10% live coral cover. Such a relationship would have implications for our expectations of resistance and recovery of reef fish communities facing an increasingly severe regime of coral reef disturbances. DOI PubMed
139. Favaro, B; Côté, IM. (2015) Do by-catch reduction devices in longline fisheries reduce capture of sharks and rays? A global meta-analysis.Fish and Fisheries 16: 300-309 Do by-catch reduction devices in longline fisheries reduce capture of sharks and rays? A global meta-analysis
BRD; discards; elasmobranch; electropositive; incidental catch; magnet
By-catch in marine fisheries, particularly those using pelagic and demersal longlines, is a major driver of declines in abundance of sharks and rays around the world. A wide variety of by-catch reduction devices (BRDs), that is, modified gears designed to reduce incidental captures of a variety of marine species while maintaining target catch rates, have been proposed, but the extent to which BRDs actually reduce the risk of catching sharks and rays remains unclear. We performed a meta-analysis of 27 publications that reported the capture of sharks and rays and, in some cases, of targeted teleosts in longline gear deployed with and without BRDs. The risk of shark and ray capture differed between types of BRDs, but only one BRD type, longlines raised off the bottom, reduced by-catch significantly. Circle hooks did not reduce the risk of capturing sharks and rays but might improve discard survival and are inexpensive, which might make them effective in reducing the detrimental effects of longlining on these species. In addition to being generally ineffective, some devices, such as electropositive and magnetic repellents, are expensive and have inherent construction drawbacks that are likely to make them unsuitable for commercial use. Overall, most BRDs did not affect the likelihood of catching targeted teleosts, but a substantial number of studies did not adequately assess target catch. We identified two poorly studied classes of BRD gear (i.e. raised demersal longlines, and monofilament nylon leaders), which represent promising directions for future research. DOI
137. Sumaila, UR; Lam, VWY; Miller, DD; Teh, L; Watson, RA; Zeller, D; Cheung, WWL; Côté, IM; Rogers, AD; Roberts, C; Sala, E; Pauly, D. (2015) Winners and losers in a world where the high seas is closed to fishing.Scientific Reports 5 Winners and losers in a world where the high seas is closed to fishing
Fishing takes place in the high seas and Exclusive Economic Zones (EEZs) of maritime countries. Closing the former to fishing has recently been proposed in the literature and is currently an issue of debate in various international fora. We determine the degree of overlap between fish caught in these two areas of the ocean, examine how global catch might change if catches of straddling species or taxon groups increase within EEZs as a result of protection of adjacent high seas; and identify countries that are likely to gain or lose in total catch quantity and value following high-seas closure. We find that <0.01% of the quantity and value of commercial fish taxa are obtained from catch taken exclusively in the high seas, and if the catch of straddling taxa increases by 18% on average following closure because of spillover, there would be no loss in global catch. The Gini coefficient, which measures income inequality, would decrease from 0.66 to 0.33. Thus, closing the high seas could be catch-neutral while inequality in the distribution of fisheries benefits among the world's maritime countries could be reduced by 50%. DOI
136. Tamburello, N; Côté, IM. (2015) Movement ecology of Indo-Pacific lionfish on Caribbean coral reefs and its implications for invasion dynamics.Biological Invasions 17: 1639-1653 Movement ecology of Indo-Pacific lionfish on Caribbean coral reefs and its implications for invasion dynamics
Lionfish; Fish; Mark-recapture; Movement; Dispersal; Landscape
The spread of marine invasive species at large geographic scales depends largely on current-driven larval dispersal. However, at smaller spatial scales, movements occurring after larval settlement can greatly influence the success of local control programs. We conducted the first dedicated tracking study of Indo-Pacific lionfish (Pterois volitans and P. miles) on Caribbean coral reefs. Using a mark-resighting approach, we estimated the scale and frequency of movements of 79 tagged lionfish on patchy and continuous reefs to study factors influencing movement. Many tagged lionfish moved relatively little, with similar to 60 % of fish resighted at least once and 10 % not moving from their initial tagging location. However, maximum movements (as far as 1.35 km in 15 days) far exceeded previous estimates. Lionfish movement was density dependent, declined at larger body sizes, and depended on seascape structure. Lionfish on continuous reefs moved faster and more often than those on patch reefs, and lionfish in patchy habitats moved farther when patches were closer together. Invasions taking place over heterogeneous seascapes such as coral reefs are difficult to manage effectively with spatially uniform regional management plans, but understanding an invader's movement ecology can help to optimize the distribution of limited resources for invasive management. DOI
135. Tamburello, N; Côté, IM; Dulvy, NK. (2015) Energy and the Scaling of Animal Space Use.American Naturalist 186: 196-211 Energy and the Scaling of Animal Space Use
allometry; home range; metabolic theory; prey handling; prey size; spatial ecology
Daily animal movements are usually limited to a discrete home range area that scales allometrically with body size, suggesting that home-range size is shaped by metabolic rates and energy availability across species. However, there is little understanding of the relative importance of the various mechanisms proposed to influence home-range scaling (e.g., differences in realm productivity, thermoregulation, locomotion strategy, dimensionality, trophic guild, and prey size) and whether these extend beyond the commonly studied birds and mammals. We derive new home-range scaling relationships for fishes and reptiles and use a model-selection approach to evaluate the generality of home-range scaling mechanisms across 569 vertebrate species. We find no evidence that home-range allometry varies consistently between aquatic and terrestrial realms or thermoregulation strategies, but we find that locomotion strategy, foraging dimension, trophic guild, and prey size together explain 80% of the variation in home-range size across vertebrates when controlling for phylogeny and tracking method. Within carnivores, smaller relative prey size among gape-limited fishes contributes to shallower scaling relative to other predators. Our study reveals how simple morphological traits and prey-handling ability can profoundly influence individual space use, which underpins broader-scale patterns in the spatial ecology of vertebrates. DOI
134. Begin, C; Brooks, G; Larson, RA; Dragicevic, S; Scharron, CER; Côté, IM. (2014) Increased sediment loads over coral reefs in Saint Lucia in relation to land use change in contributing watersheds.Ocean & Coastal Management 95: 35-45 Increased sediment loads over coral reefs in Saint Lucia in relation to land use change in contributing watersheds
Increased sedimentation is widely acknowledged to be an important stressor for Caribbean coral reefs. However, for most locations we currently lack both accurate records of changes in sediment accumulation rates over reefs as well as a quantitative link between land-based sources of sediment and sediment delivery to coastal waters. This paper aims to address this gap in our quantitative understanding of these processes for two watersheds in the island of Saint Lucia in the West Indies. We used sediment cores collected near downstream coral reefs to examine changes in sediment composition and accumulation rate over the past several decades and relied upon a GIS-based sediment budget model to estimate recent sediment yields in the two focal watersheds. Analysis of sediment cores indicated that accumulation rates of terrigenous sediment, originating from the upstream watersheds, and calcareous sediment, likely arising from dead corals, have increased 2-3 fold over the last 3-4 decades. Model-estimated changes in sediment yields between 1995 and 2010 were associated with the expansion of the unpaved road network and were congruent with measured changes in terrigenous sediment accumulation rates near the reefs over the same period. The majority (83-95%) of sediment yield in the two watersheds was attributable to unpaved and degraded roads: in fact, just four or five road segments, representing <20% of the road network in each watershed, accounted for nearly half of the estimated sediment yield in 2010. Our results suggest that unpaved roads are major sediment sources in the two study watersheds and therefore merit closer attention when implementing erosion control measures intended to reduce sediment loading into reef-bearing coastal waters. (C) 2014 Elsevier Ltd. All rights reserved. DOI
133. Côté, IM; Darling, ES; Malpica-Cruz, L; Smith, NS; Green, SJ; Curtis-Quick, J; Layman, C. (2014) What Doesn't Kill You Makes You Wary? Effect of Repeated Culling on the Behaviour of an Invasive Predator.PLOS One 9 What Doesn't Kill You Makes You Wary? Effect of Repeated Culling on the Behaviour of an Invasive Predator
As a result of being hunted, animals often alter their behaviour in ways that make future encounters with predators less likely. When hunting is carried out for conservation, for example to control invasive species, these behavioural changes can inadvertently impede the success of future efforts. We examined the effects of repeated culling by spearing on the behaviour of invasive predatory lionfish (Pterois volitans/miles) on Bahamian coral reef patches. We compared the extent of concealment and activity levels of lionfish at dawn and midday on 16 coral reef patches off Eleuthera, The Bahamas. Eight of the patches had been subjected to regular daytime removals of lionfish by spearing for two years. We also estimated the distance at which lionfish became alert to slowly approaching divers on culled and unculled reef patches. Lionfish on culled reefs were less active and hid deeper within the reef during the day than lionfish on patches where no culling had occurred. There were no differences at dawn when removals do not take place. Lionfish on culled reefs also adopted an alert posture at a greater distance from divers than lionfish on unculled reefs. More crepuscular activity likely leads to greater encounter rates by lionfish with more native fish species because the abundance of reef fish outside of shelters typically peaks at dawn and dusk. Hiding deeper within the reef could also make remaining lionfish less likely to be encountered and more difficult to catch by spearfishers during culling efforts. Shifts in the behaviour of hunted invasive animals might be common and they have implications both for the impact of invasive species and for the design and success of invasive control programs. DOI
132. Green, SJ; Côté, IM. (2014) Trait-based diet selection: prey behaviour and morphology predict vulnerability to predation in reef fish communities.Journal of Animal Ecology 83: 1451-1460 Trait-based diet selection: prey behaviour and morphology predict vulnerability to predation in reef fish communities
foraging behaviour; in situ observations; predator-prey interactions; prey characteristics; Pterois volitans; miles; resource use and availability; selective predation; stomach contents analysis
Understanding how predators select their prey can provide important insights into community structure and dynamics. However, the suite of prey species available to a predator is often spatially and temporally variable. As a result, species-specific selectivity data are of limited use for predicting novel predator-prey interactions because they are assemblage specific. We present a method for predicting diet selection that is applicable across prey assemblages, based on identifying general morphological and behavioural traits of prey that confer vulnerability to predation independent of species identity. We apply this trait-based approach to examining prey selection by Indo-Pacific lionfish (Pterois volitans and Pterois miles), invasive predators that prey upon species-rich reef fish communities and are rapidly spreading across the western Atlantic. We first generate hypotheses about morphological and behavioural traits recurring across fish species that could facilitate or deter predation by lionfish. Constructing generalized linear mixed-effects models that account for relatedness among prey taxa, we test whether these traits predict patterns of diet selection by lionfish within two independent data sets collected at different spatial scales: (i) in situ visual observations of prey consumption and availability for individual lionfish and (ii) comparisons of prey abundance in lionfish stomach contents to availability on invaded reefs at large. Both analyses reveal that a number of traits predicted to affect vulnerability to predation, including body size, body shape, position in the water column and aggregation behaviour, are important determinants of diet selection by lionfish. Small, shallow-bodied, solitary fishes found resting on or just above reefs are the most vulnerable. Fishes that exhibit parasite cleaning behaviour experience a significantly lower risk of predation than non-cleaning fishes, and fishes that are nocturnally active are at significantly greater risk. Together, vulnerable traits heighten the risk of predation by a factor of nearly 200. Our study reveals that a trait-based approach yields insights into predator-prey interactions that are robust across prey assemblages. Importantly, in situ observations of selection yield similar results to broadscale comparisons of prey use and availability, which are more typically gathered for predator species. A trait-based approach could therefore be of use across predator species and ecosystems to predict the outcomes of changing predator-prey interactions on community dynamics. DOI
131. Green, SJ; Dulvy, NK; Brooks, AML; Akins, JL; Cooper, AB; Miller, S; Côté, IM. (2014) Linking removal targets to the ecological effects of invaders: a predictive model and field test.Ecological Applications 24: 1311-1322 Linking removal targets to the ecological effects of invaders: a predictive model and field test
ecological model; eradication; exotic species; lionfish; marine management; metabolic scaling theory; population control; predation; productivity; Pterois miles; Pterois volitans; size-based analysis
Species invasions have a range of negative effects on recipient ecosystems, and many occur at a scale and magnitude that preclude complete eradication. When complete extirpation is unlikely with available management resources, an effective strategy may be to suppress invasive populations below levels predicted to cause undesirable ecological change. We illustrated this approach by developing and testing targets for the control of invasive Indo-Pacific lionfish (Pterois volitans and P. miles) on Western Atlantic coral reefs. We first developed a size-structured simulation model of predation by lionfish on native fish communities, which we used to predict threshold densities of lionfish beyond which native fish biomass should decline. We then tested our predictions by experimentally manipulating lionfish densities above or below reef-specific thresholds, and monitoring the consequences for native fish populations on 24 Bahamian patch reefs over 18 months. We found that reducing lionfish below predicted threshold densities effectively protected native fish community biomass from predation-induced declines. Reductions in density of 25-92%, depending on the reef, were required to suppress lionfish below levels predicted to overconsume prey. On reefs where lionfish were kept below threshold densities, native prey fish biomass increased by 50-70%. Gains in small (<6 cm) size classes of native fishes translated into lagged increases in larger size classes over time. The biomass of larger individuals (>15 cm total length), including ecologically important grazers and economically important fisheries species, had increased by 10-65% by the end of the experiment. Crucially, similar gains in prey fish biomass were realized on reefs subjected to partial and full removal of lionfish, but partial removals took 30% less time to implement. By contrast, the biomass of small native fishes declined by >50% on all reefs with lionfish densities exceeding reef-specific thresholds. Large inter-reef variation in the biomass of prey fishes at the outset of the study, which influences the threshold density of lionfish, means that we could not identify a single rule of thumb for guiding control efforts. However, our model provides a method for setting reef-specific targets for population control using local monitoring data. Our work is the first to demonstrate that for ongoing invasions, suppressing invaders below densities that cause environmental harm can have a similar effect, in terms of protecting the native ecosystem on a local scale, to achieving complete eradication. DOI PubMed
130. Parsons, ECM; Favaro, B; Aguirre, AA; Bauer, AL; Blight, LK; Cigliano, JA; Coleman, MA; Côté, IM; Draheim, M; Fletcher, S; Foley, MM; Jefferson, R; Jones, MC; Kelaher, BP; Lundquist, CJ; Mccarthy, JB; Nelson, A; Patterson, K; Walsh, L; Wright, AJ; Sutherland, WJ. (2014) Seventy-One Important Questions for the Conservation of Marine Biodiversity.Conservation Biology 28: 1206-1214 Seventy-One Important Questions for the Conservation of Marine Biodiversity
horizon scanning; marine biodiversity; policy; priority setting; research agenda; research questions
The ocean provides food, economic activity, and cultural value for a large proportion of humanity. Our knowledge of marine ecosystems lags behind that of terrestrial ecosystems, limiting effective protection of marine resources. We describe the outcome of 2 workshops in 2011 and 2012 to establish a list of important questions, which, if answered, would substantially improve our ability to conserve and manage the world's marine resources. Participants included individuals from academia, government, and nongovernment organizations with broad experience across disciplines, marine ecosystems, and countries that vary in levels of development. Contributors from the fields of science, conservation, industry, and government submitted questions to our workshops, which we distilled into a list of priority research questions. Through this process, we identified 71 key questions. We grouped these into 8 subject categories, each pertaining to a broad component of marine conservation: fisheries, climate change, other anthropogenic threats, ecosystems, marine citizenship, policy, societal and cultural considerations, and scientific enterprise. Our questions address many issues that are specific to marine conservation, and will serve as a road map to funders and researchers to develop programs that can greatly benefit marine conservation. DOI PubMed
129. Begin, C; Wurzbacher, J; Côté, IM. (2013) Variation in benthic communities of eastern Caribbean coral reefs in relation to surface sediment composition.Marine Biology 160: 343-353 Variation in benthic communities of eastern Caribbean coral reefs in relation to surface sediment composition
GREAT-BARRIER-REEF; US-VIRGIN-ISLANDS; SPONGE ASSEMBLAGES; ST-JOHN; POCILLOPORA-DAMICORNIS; PUERTO-RICO; IMPACTS; TERRESTRIAL; RUNOFF; ECOLOGY
The effects of sedimentation on coral reefs are commonly studied at local scales, but larger-scale patterns have been elusive, making it difficult to determine the role of sedimentation in region-wide changes in these ecosystems. We examined the relationships between characteristics of reef-associated surface sediment and benthic composition of 22 reefs around 11 islands of the eastern Caribbean. The terrigenous fraction in surface sediment increased with proximity to a clear source of sediment input. The percent cover of live coral, macroalgae, and turf algae decreased with higher terrigenous sediment fraction, while sponge cover increased. Sites with sediment containing high and low terrigenous fraction differed in coral species assemblages. In particular, the cover of Montastraea annularis complex decreased with increasing terrigenous sediment fraction. The proportion of fine-grained sediment had no effect on benthic composition. These results suggest that sedimentation may play a role in shaping coral reef communities at a regional scale. DOI
127. Côté, IM. (2013) Inadvertent consequences of fishing: the case of the sex-changing shrimp.Journal of Animal Ecology 82: 495-497 Inadvertent consequences of fishing: the case of the sex-changing shrimp
SELECTIVE HARVEST; CONSERVATION; POPULATIONS; CASCADES; DYNAMICS; ANIMALS; GROWTH; SIZE
The Hokkai shrimp Pandalus latirostris starts life as a male, but eventually turns into a female given the right size and social conditions. The traps used in the fishery targeting this species selectively retain the larger females, leaving a severely male-biased sex ratio in nature and social conditions that bear no resemblance to those that prompted (or prevented) sex change. Photo: Susumu Chiba Chiba, S., Yoshino, K., Kanaiwa, M., Kawajiri, T. & Goshima, S. (2013) Maladaptive sex ratio adjustment by a sex-changing shrimp in selective fishing environments. Journal of Animal Ecology, 82, 631640. Fishing can have many unintended consequences. In this issue, Chiba etal. () demonstrate that size-selective harvesting of a sex-changing shrimp effectively voids their normally adaptive adjustments to population sex ratio. The shrimp's decision' to change sex depends largely on the relative abundance of mature males and females in early summer, before fishing begins. However, fishing traps selectively retain females, leading to heavily male-biased sex ratios at the onset of autumn breeding that are different from the ratios that influenced sex-change decisions. Although this phenomenon is not yet expressed in catch trends, maladaptive sex-change decisions could ultimately affect population productivity and persistence. DOI
126. Côté, IM; Green, SJ; Hixon, MA. (2013) Predatory fish invaders: Insights from Indo-Pacific lionfish in the western Atlantic and Caribbean.Biological Conservation 164: 50-61 Predatory fish invaders: Insights from Indo-Pacific lionfish in the western Atlantic and Caribbean
The invasion of western Atlantic marine habitats by two predatory Indo-Pacific lionfish, Pterois volitans and P. miles, has recently unfolded at an unprecedented rate, with ecological consequences anticipated to be largely negative. We take stock of recently accumulated knowledge about lionfish ecology and behaviour and examine how this information is contributing to our general understanding of the patterns and processes underpinning marine predator invasions, and to the specific issue of lionfish management. Lionfish were first reported off Florida in 1985. Since their establishment in The Bahamas in 2004, they have colonised 7.3 million km(2) of the western Atlantic and Caribbean region, and populations have grown exponentially at many locations. These dramatic increases potentially result from a combination of life-history characteristics of lionfish, including early maturation, early reproduction, anti-predatory defenses, unique predatory behaviour, and ecological versatility, as well as features of the recipient communities, including prey naivete, weak competitors, and native predators that are overfished and naive to lionfish. Lionfish have reduced the abundance of small native reef fishes by up to 95% at some invaded sites. Population models predict that culling can reduce lionfish abundance substantially, but removal rates must be high. Robust empirical estimates of the cost-effectiveness and effects of removal strategies are urgently needed because lionfish management will require a long-term, labour-intensive effort that may be possible only at local scales. The ultimate causes of the invasion were inadequate trade legislation and poor public awareness of the effects of exotic species on marine ecosystems. The lionfish invasion highlights the need for prevention, early detection, and rapid response to marine invaders. (C) 2013 Elsevier Ltd. All rights reserved. DOI
125. Côté, IM; Green, SJ; Morris, JA; Akins, JL; Steinke, D. (2013) Diet richness of invasive Indo-Pacific lionfish revealed by DNA barcoding.Marine Ecology Progress Series 472: 249-256 Diet richness of invasive Indo-Pacific lionfish revealed by DNA barcoding
CORAL-REEF FISHES; PTEROIS-VOLITANS; IDENTIFICATION; CONSEQUENCES; EXTINCTION; INSIGHTS; BAHAMAS; FOREST; COAST; SNAKE
Indo-Pacific lionfish Pterois spp. have recently invaded marine habitats throughout the western Atlantic, Gulf of Mexico, and Caribbean Sea. Their unusual hunting behaviour suggests that they could prey on most fish species within their gape size limits. However, few prey species have been identified so far due to the challenges of identifying partly digested prey. Moreover, it is not clear how well the identifiable diet reflects the unidentified portion. To address these issues, we DNA-barcoded unidentifiable fish items from the stomachs of 130 lionfish captured on Bahamian coral reefs. We identified 37 fish prey species, nearly half of which had not previously been recorded in this region. The total richness of lionfish prey fish recorded so far may represent up to similar to 54% of potential prey species on the study reefs. The relative importance of prey species in the visually identifiable diet portion, which was limited to 25% of prey items, differed from that in the 'unidentifiable' portion, which was largely resolved here with barcoding, weakening extra-polations from visual identification. The high diet resolution afforded by barcoding can increase our ability to predict the impacts of invasive predators on recipient communities. DOI
124. Darling, ES; McClanahan, TR; Côté, IM. (2013) Life histories predict coral community disassembly under multiple stressors.Global Change Biology 19: 1930-1940 Life histories predict coral community disassembly under multiple stressors
MARINE PROTECTED AREAS; WESTERN INDIAN-OCEAN; REGION-WIDE DECLINES; CLIMATE-CHANGE; REEF CORALS; TEMPERATURE-VARIATION; GLOBAL ANALYSIS; KENYAN REEFS; COLONY SIZE; ECOSYSTEMS
Climate change is reshaping biological communities against a background of existing human pressure. Evaluating the impacts of multiple stressors on community dynamics can be particularly challenging in species-rich ecosystems, such as coral reefs. Here, we investigate whether life-history strategies and cotolerance to different stressors can predict community responses to fishing and temperature-driven bleaching using a 20-year time series of coral assemblages in Kenya. We found that the initial life-history composition of coral taxa largely determined the impacts of bleaching and coral loss. Prior to the 1998 bleaching event, coral assemblages within no-take marine reserves were composed of three distinct life histories competitive, stress-tolerant and weedy and exhibited strong declines following bleaching with limited subsequent recovery. In contrast, fished reefs had lower coral cover, fewer genera and were composed of stress-tolerant and weedy corals that were less affected by bleaching over the long term. Despite these general patterns, we found limited evidence for cotolerance as coral genera and life histories were variable in their sensitivities to fishing and bleaching. Overall, fishing and bleaching have reduced coral diversity and led to altered coral communities of survivor' species with stress-tolerant and weedy life histories. Our findings are consistent with expectations that climate change interacting with existing human pressure will result in the loss of coral diversity and critical reef habitat. DOI
123. Favaro, B; Duff, SD; Côté, IM. (2013) A trap with a twist: evaluating a bycatch reduction device to prevent rockfish capture in crustacean traps.ICES Journal of Marine Science 70: 114-122 A trap with a twist: evaluating a bycatch reduction device to prevent rockfish capture in crustacean traps
behaviour; catch comparison; fishing gear; selectivity; underwater filming
Bycatch, or the incidental capture of non-target species, occurs in fisheries around the world, with often detrimental ecological consequences. Bycatch reduction devices (BRDs) that increase catch specificity have been used successfully in some fisheries, and the development of such devices remains an important component of the global effort to reduce bycatch rates. We tested novel devices designed to exclude juvenile rockfish (Sebastes spp.) from traps used to catch spot prawns (Pandalus platyceros), a commercially important species in British Columbia, Canada. The devices included reductions in trap opening sizes and novel bent-tunnel openings. Reducing trap opening size did not affect bycatch rates of rockfish or other non-target fish species. In contrast, bent-tunnel BRDs eliminated rockfish bycatch, and two of the bent-tunnel variants also excluded other fish species. However, prawn catch rates were reduced in all modified gear, and large prawns were often excluded more than small prawns. Videos recorded in situ revealed that prawn attempts to enter traps took longer and were more likely to fail in BRD-equipped than in unmodified traps. We conclude that bent-tunnel BRDs have the potential to be useful, but improvements are needed to increase prawn catch to levels similar to that of unmodified traps. DOI
122. Green, SJ; Tamburello, N; Miller, SE; Akins, JL; Côté, IM. (2013) Habitat complexity and fish size affect the detection of Indo-Pacific lionfish on invaded coral reefs.Coral Reefs 32: 413-421 Habitat complexity and fish size affect the detection of Indo-Pacific lionfish on invaded coral reefs
UNDERWATER VISUAL-CENSUS; ABUNDANCE; INVASION; DENSITY; ASSEMBLAGES; POPULATIONS; ATLANTIC; BEHAVIOR
A standard approach to improving the accuracy of reef fish population estimates derived from underwater visual censuses (UVCs) is the application of species-specific correction factors, which assumes that a species' detectability is constant under all conditions. To test this assumption, we quantified detection rates for invasive Indo-Pacific lionfish (Pterois volitans and P. miles), which are now a primary threat to coral reef conservation throughout the Caribbean. Estimates of lionfish population density and distribution, which are essential for managing the invasion, are currently obtained through standard UVCs. Using two conventional UVC methods, the belt transect and stationary visual census (SVC), we assessed how lionfish detection rates vary with lionfish body size and habitat complexity (measured as rugosity) on invaded continuous and patch reefs off Cape Eleuthera, the Bahamas. Belt transect and SVC surveys performed equally poorly, with both methods failing to detect the presence of lionfish in > 50 % of surveys where thorough, lionfish-focussed searches yielded one or more individuals. Conventional methods underestimated lionfish biomass by similar to 200 %. Crucially, detection rate varied significantly with both lionfish size and reef rugosity, indicating that the application of a single correction factor across habitats and stages of invasion is unlikely to accurately characterize local populations. Applying variable correction factors that account for site-specific lionfish size and rugosity to conventional survey data increased estimates of lionfish biomass, but these remained significantly lower than actual biomass. To increase the accuracy and reliability of estimates of lionfish density and distribution, monitoring programs should use detailed area searches rather than standard visual survey methods. Our study highlights the importance of accounting for sources of spatial and temporal variation in detection to increase the accuracy of survey data from coral reef systems. DOI
121. Hackerott, S; Valdivia, A; Green, SJ; Côté, IM; Cox, CE; Akins, L; Layman, CA; Precht, WF; Bruno, JF. (2013) Native Predators Do Not Influence Invasion Success of Pacific Lionfish on Caribbean Reefs.PLOS One 8 Native Predators Do Not Influence Invasion Success of Pacific Lionfish on Caribbean Reefs
EXOTIC PLANT INVASIONS; REGION-WIDE DECLINES; CORAL-REEF; COMMUNITIES; RECRUITMENT; ABUNDANCE; ATLANTIC; ECOLOGY
Biotic resistance, the process by which new colonists are excluded from a community by predation from and/or competition with resident species, can prevent or limit species invasions. We examined whether biotic resistance by native predators on Caribbean coral reefs has influenced the invasion success of red lionfishes (Pterois volitans and Pterois miles), piscivores from the Indo-Pacific. Specifically, we surveyed the abundance (density and biomass) of lionfish and native predatory fishes that could interact with lionfish (either through predation or competition) on 71 reefs in three biogeographic regions of the Caribbean. We recorded protection status of the reefs, and abiotic variables including depth, habitat type, and wind/wave exposure at each site. We found no relationship between the density or biomass of lionfish and that of native predators. However, lionfish densities were significantly lower on windward sites, potentially because of habitat preferences, and in marine protected areas, most likely because of ongoing removal efforts by reserve managers. Our results suggest that interactions with native predators do not influence the colonization or post-establishment population density of invasive lionfish on Caribbean reefs. DOI
120. Schultz, JA; Darling, ES; Côté, IM. (2013) What is an endangered species worth? Threshold costs for protecting imperilled fishes in Canada.Marine Policy 42: 125-132 What is an endangered species worth? Threshold costs for protecting imperilled fishes in Canada
RISK; CONSERVATION; BIODIVERSITY; EXTINCTION; COLLAPSE; SCIENCE; THREATS
The protection of imperilled fish species is increasingly urgent given ongoing fisheries declines and the degradation of aquatic habitats. In Canada, threatened aquatic species were less likely than terrestrial species to be listed under the Species at Risk Act (SARA), the main legal instrument for bestowing protection, in the early years of the Act's implementation. In this paper, the existence of economic thresholds that might have hampered the protection of Canadian marine and freshwater fishes is examined. The analysis of the socio-economic data used to inform listing decisions about threatened fish taxa over the past decade reveals that the likelihood of being listed declines non-linearly with increasing estimated costs of protection but does not vary with proposed threat status. The estimated threshold cost (i.e., the point at which the likelihood of not being listed=0.5) was similar to$5,000,000 (similar to$1,400,000 to similar to$31,400,000, 95% Cl) per decade for freshwater species but only similar to$90,000 (similar to$-50,000 to similar to$140,000, 95% Cl) per decade for marine fish taxa. In fact, no marine fish species with an anticipated cost of listing greater than zero was listed for protection. The presence of existing management legislation and qualitative statements about negative impacts of listing on exploitation generally led to denying protection to marine but not to freshwater species. These findings highlight both a large and inconsistent emphasis on costs of protection in SARA listing decisions, to the detriment of marine fish species. (C) 2013 Elsevier Ltd. All rights reserved. DOI
119. Soares, MC; Cardoso, SC; Nicolet, KJ; Côté, IM; Bshary, R. (2013) Indo-Pacific parrotfish exert partner choice in interactions with cleanerfish but Caribbean parrotfish do not.Animal Behaviour 86: 611-615 Indo-Pacific parrotfish exert partner choice in interactions with cleanerfish but Caribbean parrotfish do not
CLIENT REEF FISH; LABROIDES-DIMIDIATUS; TACTILE STIMULATION; CLEANING GOBIES; SERVICE QUALITY; CONTROL MECHANISMS; MUTUALISM; COOPERATION; PUNISHMENT; EVOLUTION
Cooperation theory puts a strong emphasis on partner control mechanisms that have evolved to stabilize cooperation against the temptation of cheating. The marine cleaning mutualism between the Indo-Pacific bluestreack cleaner wrasse, Labroides dimidiatus, and its reef fish 'clients' has been a model system to study partner control mechanisms and counterstrategies. These cleaners cooperate by eating ectoparasites; however, they can cheat by taking client mucus, which they prefer. Such a conflict may be the exception. For example, Caribbean cleaning gobies, Elacatinus spp., prefer to eat ectoparasites instead of mucus. While partner control mechanisms and counterstrategies seem to be absent in cleaning gobies, no study has directly compared cleaner wrasses and cleaning gobies by using the same methods. We examined systematic differences in cleaning interaction patterns and strategic behaviour exhibited by 12 closely related parrotfish species in the two systems. Parrotfish seeking cleaner wrasses visited them more often and spent more time with their cleaner than parrotfish seeking cleaning gobies. Moreover, the clients of cleaner wrasses returned more often to the same cleaner following a positive interaction, whereas the clients of cleaning gobies were less influenced by the outcome of previous interactions. We hypothesize that the higher frequency and repeated nature of interactions observed in the cleaner wrasse system, combined with the need to resolve conflicts, might have been prerequisites for the development of complex behavioural strategies. (C) 2013 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved. DOI
118. Côté, IM; Green, SJ. (2012) Potential effects of climate change on a marine invasion: The importance of current context.Current Zoology 58: 1-8 Potential effects of climate change on a marine invasion: The importance of current context
Non-indigenous species; Coral reefs; Dispersal; Ecological impacts of invasion
Species invasions threaten marine biodiversity globally. There is a concern that climate change is exacerbating this problem. Here, we examined some of the potential effects of warming water temperatures on the invasion of Western Atlantic habitats by a marine predator, the Indo-Pacific lionfish (Pterois volitans and P. miles). We focussed on two temperature-dependent aspects of lionfish life-history and behaviour: pelagic larval duration, because of its link to dispersal potential, and prey consumption rate, because it is an important determinant of the impacts of lionfish on native prey. Using models derived from fundamental metabolic theory, we predict that the length of time spent by lionfish in the plankton in early life should decrease with warming temperatures, with a concomitant reduction in potential dispersal distance. Although the uncertainty around change in dispersal distances is large, predicted reductions are, on average, more than an order of magnitude smaller than the current rate of range expansion of lionfish in the Caribbean. Nevertheless, because shorter pelagic larval duration has the potential to increase local retention of larvae, local lionfish management will become increasingly important under projected climate change. Increasing temperature is also expected to worsen the current imbalance between rates of prey consumption by lionfish and biomass production by their prey, leading to a heightened decline in native reef fish biomass. However, the magnitude of climate-induced decline is predicted to be minor compared to the effect of current rates of lionfish population increases (and hence overall prey consumption rates) on invaded reefs. Placing the predicted effects of climate change in the current context thus reveals that, at least for the lionfish invasion, the threat is clear and present, rather than future [Current Zoology 58 (1): 1-8, 2012].
116. Darling, ES; Alvarez-Filip, L; Oliver, TA; McClanahan, TR; Côté, IM. (2012) Evaluating life-history strategies of reef corals from species traits.Ecology Letters 15: 1378-1386 Evaluating life-history strategies of reef corals from species traits
Community assembly; coral reefs; C-S-R triangle; ecological strategies; functional diversity; selection pressure
Classifying the biological traits of organisms can test conceptual frameworks of life-history strategies and allow for predictions of how different species may respond to environmental disturbances. We apply a trait-based classification approach to a complex and threatened group of species, scleractinian corals. Using hierarchical clustering and random forests analyses, we identify up to four life-history strategies that appear globally consistent across 143 species of reef corals: competitive, weedy, stress-tolerant and generalist taxa, which are primarily separated by colony morphology, growth rate and reproductive mode. Documented shifts towards stress-tolerant, generalist and weedy species in coral reef communities are consistent with the expected responses of these life-history strategies. Our quantitative trait-based approach to classifying life-history strategies is objective, applicable to any taxa and a powerful tool that can be used to evaluate theories of community ecology and predict the impact of environmental and anthropogenic stressors on species assemblages. DOI
115. Favaro, B; Lichota, C; Côté, IM; Duff, SD. (2012) TrapCam: an inexpensive camera system for studying deep-water animals.Methods in Ecology and Evolution 3: 39-46 TrapCam: an inexpensive camera system for studying deep-water animals
behaviour; bycatch; deep water; digital video; rockfish; spot prawn; underwater cameras
1. Behavioural research in deep water (>40 m depth) has traditionally been expensive and logistically challenging, particularly because the light and sound produced by underwater vehicles make them unsuitably disruptive. Yet, understanding the behaviour of deep-water animals, especially those targeted by exploitation, is important for conservation. For example, understanding interactions between animals and deep-water fishing gear could inform the design of devices that minimize bycatch. 2. We describe the ` TrapCam', a self- contained, high- definition video system that requires neither the support of a vessel once deployed nor special equipment to deploy or retrieve. This system can record 13-h videos at 1080p resolution and is deployable on any substrata at depths of up to 100 m. The system is inexpensive (<$ 3000 USD), versatile and suited to the study of animal behaviour at depths inaccessible to scuba divers. 3. We evaluate the performance and cost effectiveness of TrapCam and analyse videos retrieved frompilot deployments to observe spot prawn (Pandalus platyceros) traps at 100 mdepth. Preliminary analyses of animal- prawn trap interactions yield novel insights. We provide future directions for researchers to use this type of camera system to study deep water- dwelling species around the world. DOI
113. Green, SJ; Akins, JL; Maljkovic, A; Côté, IM. (2012) Invasive Lionfish Drive Atlantic Coral Reef Fish Declines.PLOS One 7 Invasive Lionfish Drive Atlantic Coral Reef Fish Declines
Indo-Pacific lionfish (Pterois volitans and P. miles) have spread swiftly across the Western Atlantic, producing a marine predator invasion of unparalleled speed and magnitude. There is growing concern that lionfish will affect the structure and function of invaded marine ecosystems, however detrimental impacts on natural communities have yet to be measured. Here we document the response of native fish communities to predation by lionfish populations on nine coral reefs off New Providence Island, Bahamas. We assessed lionfish diet through stomach contents analysis, and quantified changes in fish biomass through visual surveys of lionfish and native fishes at the sites over time. Lionfish abundance increased rapidly between 2004 and 2010, by which time lionfish comprised nearly 40% of the total predator biomass in the system. The increase in lionfish abundance coincided with a 65% decline in the biomass of the lionfish's 42 Atlantic prey fishes in just two years. Without prompt action to control increasing lionfish populations, similar effects across the region may have long-term negative implications for the structure of Atlantic marine communities, as well as the societies and economies that depend on them. DOI
112. Hutchings, J.A., Côté, I.M., Dodson, J.J., Fleming, I.A., Jennings, S., Mantua, N.J., Peterman, R.M., Riddell, B.E., Weaver, A.J. (2012) Climate change, fisheries, and Aquaculture: Trends and consequences for Canadian marine biodiversity.Environmental Reviews 20, 220-311. Climate change, fisheries, and Aquaculture: Trends and consequences for Canadian marine biodiversity.
Climate change, fishing, and aquaculture have affected and will continue to influence Canadian marine biodiversity, albeit at different spatial scales. The Arctic is notably affected by reduced quality and quantity of sea ice caused by global warming, and by concomitant and forecasted changes in ocean productivity, species ecology, and human activity. The Atlantic has been especially impacted by severe overfishing and human-induced alterations to food webs. Climate change, fishing, and aquaculture have all affected, to varying degrees, biodiversity on Canada's Pacific coast. Past and projected trends in key biodiversity stressors reveal marked change. Oceanographic trends include increasing surface water temperatures, reduced salinity, increased acidity, and, in some areas, reduced oxygen. Reductions in Canada's fishery catches (those in 2009 were half those of the late 1980s), followed by reductions in fishing pressure, are associated with dramatic changes in the species composition of commercial catches in the Atlantic (formerly groundfish, now predominantly invertebrates and pelagic fish) and the Pacific (formerly salmon, now predominantly groundfish). Aquaculture, dominated by the farming of Atlantic salmon, grew rapidly from the early 1980s until 2002 and has since stabilized. Climate change is forecast to affect marine biodiversity by shifting species distributions, changing species community composition, decoupling the timing of species' resource requirements and resource availability, and reducing habitat quality. Harvest-related reductions in fish abundance, many by 80% or more, coupled with fishing-induced changes to food webs, are impairing the capacity of species to recover or even persist. Open-sea aquaculture net pens affect biodiversity by ( i) habitat alteration resulting from organic wastes, chemical inputs, and use of nonnative species; ( ii) exchange of pathogens between farmed and wild species; and ( iii) interbreeding between wild fish and farmed escapees. Physical and biological changes in the oceans, along with direct anthropogenic impacts, are modifying Canadian marine biodiversity with implications for food security and the social and economic well-being of coastal communities. To assess the consequences of changes in biodiversity for Canada's oceans and society, it is necessary to understand the current state of marine biodiversity and how it might be affected by projected changes in climate and human uses. DOI
111. Hutchings, JA; Côté, IM; Dodson, JJ; Fleming, IA; Jennings, S; Mantua, NJ; Peterman, RM; Riddell, BE; Weaver, AJ; VanderZwaag, DL. (2012) Is Canada fulfilling its obligations to sustain marine biodiversity? A summary review, conclusions, and recommendations.Environmental Reviews 20: 353-361 Is Canada fulfilling its obligations to sustain marine biodiversity? A summary review, conclusions, and recommendations
Canada has made numerous national and international commitments to sustain marine biodiversity. Given current and potential threats to biodiversity from climate change, fisheries, and aquaculture, we provide a summary review of Canada's progress in fulfilling its obligations to protect, conserve, recover, and responsibly exploit marine biodiversity. We conclude that Canada has made little substantive progress, when compared to most developed nations, in meeting its biodiversity commitments. Much of Canada's policy and rhetoric has not been operationalised, leaving many of the country's national and international obligations unfulfilled in some key areas, such as the establishment of marine protected areas and incorporation of the precautionary approach to fisheries management. We conclude that regulatory conflict within Canada's Department of Fisheries and Oceans (DFO) and the absolute discretion exercised by the national Minister of Fisheries and Oceans contribute significantly to an unduly slow rate of policy and statute implementation. We recommend new approaches and measures to sustain Canadian marine biodiversity and new research initiatives to support scientific advice to decision-makers. Many recommendations focus on management actions required to meet existing commitments to biodiversity conservation. Overall, we conclude that the most effective strategy is to protect existing biological diversity and to rebuild depleted populations and species to restore natural diversity. By improving and protecting the biodiversity in Canada's oceans, such a strategy will restore the natural resilience of Canada's ocean ecosystems to adapt to the challenges posed by climate change and other anthropogenic activities with consequent long-term benefits for food security and social and economic well-being.Website DOI
109. Reynolds, J.D., Favaro, B. & Côté. (2012) Canada: A bleak day for the environment.Nature 487, 171 Canada: A bleak day for the environment
It was a dark day for environmental science and policy in Canada on 29 June.
The country's Conservative Party has been steadily dismantling environmental protection since winning a majority government last year (see, for example, Nature http://doi.org/h2v; 2012). Further alarming changes to environmental laws were concealed in a 'budget bill' that was ratified by the Senate on 29 June.
For example, the Canadian Environmental Assessment Act has been replaced by a weaker law that reduces government oversight of the environmental impact of a proposed pipeline from the Alberta oil sands to tankers off British Columbia. Canada's Fisheries Act now allows for more pollution and no longer protects fish habitats, except for fisheries. The National Round Table on the Environment and the Economy, which provides independent scientific advice on sustainable development, will be dissolved in March 2013. A finance committee that had no scientific or public input has decided that this massive legislative overhaul could proceed as written.
Globally significant research facilities have already been axed, including the renowned Experimental Lakes Area and the Polar Environment Atmospheric Research Laboratory in the high Arctic. Scientific agencies such as Fisheries and Oceans Canada (DFO), Environment Canada and Parks Canada have had to sack most of the personnel responsible for habitat management and monitoring, including those in the DFO's marine-pollution programme.
The new legislative framework marginalizes science in environmental management, and could do irreparable harm to the environment and the economy it supports. Such tactics match Canada's intransigence on climate change: the same bill made it the first country to pull out of the Kyoto agreement.Website DOI
108. Soares, MC; Bshary, R; Cardoso, SC; Côté, IM; Oliveira, RF. (2012) Face Your Fears: Cleaning Gobies Inspect Predators despite Being Stressed by Them.PLOS One 7 Face Your Fears: Cleaning Gobies Inspect Predators despite Being Stressed by Them
Social stressors typically elicit two distinct behavioural responses in vertebrates: an active response (i.e., "fight or flight") or behavioural inhibition (i.e., freezing). Here, we report an interesting exception to this dichotomy in a Caribbean cleaner fish, which interacts with a wide variety of reef fish clients, including predatory species. Cleaning gobies appraise predatory clients as potential threat and become stressed in their presence, as evidenced by their higher cortisol levels when exposed to predatory rather than to non-predatory clients. Nevertheless, cleaning gobies neither flee nor freeze in response to dangerous clients but instead approach predators faster (both in captivity and in the wild), and interact longer with these clients than with non-predatory clients (in the wild). We hypothesise that cleaners interrupt the potentially harmful physiological consequences elicited by predatory clients by becoming increasingly proactive and by reducing the time elapsed between client approach and the start of the interaction process. The activation of a stress response may therefore also be responsible for the longer cleaning service provided by these cleaners to predatory clients in the wild. Future experimental studies may reveal similar patterns in other social vertebrate species when, for instance, individuals approach an opponent for reconciliation after a conflict. DOI
107. Sutherland, WJ; Aveling, R; Bennun, L; Chapman, E; Clout, M; Côté, IM; Depledge, MH; Dicks, LV; Dobson, AP; Fellman, L; Fleishman, E; Gibbons, DW; Keim, B; Lickorish, F; Lindenmayer, DB; Monk, KA; Norris, K; Peck, LS; Prior, SV; Scharlemann, JPW; Spalding, M; Watkinson, AR. (2012) A horizon scan of global conservation issues for 2012.Trends in Ecology & Evolution 27: 12-18 A horizon scan of global conservation issues for 2012
Our aim in conducting annual horizon scans is to identify issues that, although currently receiving little attention, may be of increasing importance to the conservation of biological diversity in the future. The 15 issues presented here were identified by a diverse team of 22 experts in horizon scanning, and conservation science and its application. Methods for identifying and refining issues were the same as in two previous annual scans and are widely transferable to other disciplines. The issues highlight potential changes in climate, technology and human behaviour. Examples include warming of the deep sea, increased cultivation of perennial grains, burning of Arctic tundra, and the development of nuclear batteries and hydrokinetic in-stream turbines. DOI
106. Alvarez-Filip, L; Côté, IM; Gill, JA; Watkinson, AR; Dulvy, NK. (2011) Region-wide temporal and spatial variation in Caribbean reef architecture: is coral cover the whole story?Global Change Biology 17: 2470-2477 Region-wide temporal and spatial variation in Caribbean reef architecture: is coral cover the whole story?
climate change; ecosystem services; foundation species; habitat loss; reef degradation
The architectural complexity of coral reefs is largely generated by reef-building corals, yet the effects of current regional-scale declines in coral cover on reef complexity are poorly understood. In particular, both the extent to which declines in coral cover lead to declines in complexity and the length of time it takes for reefs to collapse following coral mortality are unknown. Here we assess the extent of temporal and spatial covariation between coral cover and reef architectural complexity using a Caribbean-wide dataset of temporally replicated estimates spanning four decades. Both coral cover and architectural complexity have declined rapidly over time, with little evidence of a time-lag. However, annual rates of change in coral cover and complexity do not covary, and levels of complexity vary greatly among reefs with similar coral cover. These findings suggest that the stressors influencing Caribbean reefs are sufficiently severe and widespread to produce similar regional-scale declines in coral cover and reef complexity, even though reef architectural complexity is not a direct function of coral cover at local scales. Given that architectural complexity is not a simple function of coral cover, it is important that conservation monitoring and restoration give due consideration to both architecture and coral cover. This will help ensure that the ecosystem services supported by architectural complexity, such as nutrient recycling, dissipation of wave energy, fish production and diversity, are maintained and enhanced. DOI
105. Alvarez-Filip, L; Dulvy, NK; Côté, IM; Watkinson, AR; Gill, JA. (2011) Coral identity underpins architectural complexity on Caribbean reefs.Ecological Applications 21: 2223-2231 Coral identity underpins architectural complexity on Caribbean reefs
biodiversity; coral; Cozumel; Mexico; dominance; functional groups; habitat complexity; landscape ecology; reef
The architectural complexity of ecosystems can greatly influence their capacity to support biodiversity and deliver ecosystem services. Understanding the components underlying this complexity can aid the development of effective strategies for ecosystem conservation. Caribbean coral reefs support and protect millions of livelihoods, but recent anthropogenic change is shifting communities toward reefs dominated by stress-resistant coral species, which are often less architecturally complex. With the regionwide decline in reef fish abundance, it is becoming increasingly important to understand changes in coral reef community structure and function. We quantify the influence of coral composition, diversity, and morpho-functional traits on the architectural complexity of reefs across 91 sites at Cozumel, Mexico. Although reef architectural complexity increases with coral cover and species richness, it is highest on sites that are low in taxonomic evenness and dominated by morpho-functionally important, reef-building coral genera, particularly Montastraea. Sites with similar coral community composition also tend to occur on reefs with very similar architectural complexity, suggesting that reef structure tends to be determined by the same key species across sites. Our findings provide support for prioritizing and protecting particular reef types, especially those dominated by key reef-building corals, in order to enhance reef complexity. DOI
104. Alvarez-Filip, L; Gill, JA; Dulvy, NK; Perry, AL; Watkinson, AR; Côté, IM. (2011) Drivers of region-wide declines in architectural complexity on Caribbean reefs.Coral Reefs 30: 1051-1060 Drivers of region-wide declines in architectural complexity on Caribbean reefs
Coral bleaching; Drivers of change; Environmental change; Ecosystem services; Habitat complexity; Hurricanes; Marine reserves; Reef degradation
Severe declines in the cover of live hard coral on reefs have been reported worldwide, and in the Caribbean region, the architectural complexity of coral reefs has also declined markedly. While the drivers of coral cover loss are relatively well understood, little is known about the drivers of regional-scale declines in architectural complexity. We have used a dataset of 49 time series reporting reef architectural complexity to explore the effect of hurricanes, coral bleaching and fishing on Caribbean-wide annual rates of change in reef complexity. Hurricane impacts greatly influence reef complexity, with the most rapid rates of decline in complexity occurring at sites impacted during their survey period, and with lower rates of loss occurring at unimpacted sites. Reef architectural complexity did not change significantly following mass bleaching events (in a time frame of < 5 years) or positive thermal anomalies. Although the rates of change in architectural complexity were similar in and out of marine protected areas (MPAs), significant declines in complexity were observed inside but not outside of MPAs, possibly because reductions in fishing can lead to increased bioerosion by herbivores within MPAs. Our findings suggest that major drivers of coral mortality, such as coral bleaching, do not influence reef architectural complexity in the short term (< 5 years). Instead, direct physical impacts and reef bioerosion appear to be important drivers of the widespread loss of architecturally complex reefs in the Caribbean. DOI
102. Darling, ES; Green, SJ; O'Leary, JK; Côté, IM. (2011) Indo-Pacific lionfish are larger and more abundant on invaded reefs: a comparison of Kenyan and Bahamian lionfish populations.Biological Invasions 13: 2045-2051 Indo-Pacific lionfish are larger and more abundant on invaded reefs: a comparison of Kenyan and Bahamian lionfish populations
Comparative studies; Exotic species; Lionfish; Ecological release; Native-invasive comparison; Size release
The invasion by Indo-Pacific lionfish (Pterois volitans and P. miles) of the western Atlantic, Caribbean and Gulf of Mexico is emerging as a major threat to coral reef communities across the region. Comparing native and introduced populations of invasive species can reveal shifts in ecology and behaviour that can accompany successful invasions. Using standardized field surveys replicated at multiple sites in Kenya and the Bahamas, we present the first direct comparisons of lionfish density, body size, biomass and behaviour between native and invaded coral reefs. We found that lionfish occur at higher densities with larger body sizes and total biomass on invaded Bahamian coral reefs than the ecologically equivalent species (P. miles) does on native Kenyan reefs. However, the combined average density of the five lionfish species (Pterois miles, P. antennata, P. radiata, Dendrochirus brachypterus and D. zebra) on Kenyan reefs was similar to the density of invasive lionfish in the Bahamas. Understanding the ecological processes that drive these differences can help inform the management and control of invasive lionfish. DOI
101. Green, SJ; Akins, JL; Côté, IM. (2011) Foraging behaviour and prey consumption in the Indo-Pacific lionfish on Bahamian coral reefs.Marine Ecology-Progress Series 433: 159-167 Foraging behaviour and prey consumption in the Indo-Pacific lionfish on Bahamian coral reefs
Pterois volitans; Marine invasion; Predation rates; Daily pattern; Behavioural; observations
Predicting and mitigating the effects of invasive Indo-Pacific lionfish Pterois volitans on Caribbean fish communities requires a thorough understanding of the species' predation behaviour in the invaded range, including the types and amounts of prey consumed and how foraging patterns vary in relation to extrinsic conditions. We studied the activity levels and prey consumption rates of lionfish on 12 shallow coral reefs in the Bahamas in relation to time of day and prey availability. Lionfish predation rates and activity levels were significantly higher during crepuscular (dawn and dusk) periods than at mid-day. Available prey fish biomass was highest at dawn but lower at mid-day and dusk, suggesting that lionfish predation activity is not limited by prey availability alone. Our calculated average daily mass-specific prey consumption rates, which incorporated daily variation, was similar to 3 times the estimates obtained from studies of captive lionfish in their native range and of invasive lionfish observed only during the day. Our results will help to predict more accurately the effect of predation by invasive lionfish on native reef fish communities. DOI
100. Holt, BG; Côté, IM; Emerson, BC. (2011) Searching for Speciation Genes: Molecular Evidence for Selection Associated with Colour Morphotypes in the Caribbean Reef Fish Genus Hypoplectrus.PLOS One 6 Searching for Speciation Genes: Molecular Evidence for Selection Associated with Colour Morphotypes in the Caribbean Reef Fish Genus Hypoplectrus
Closely related species that show clear phenotypic divergence, but without obvious geographic barriers, can provide opportunities to study how diversification can occur when opportunities for allopatric speciation are limited. We examined genetic divergence in the coral reef fish genus Hypoplectrus (family: Serranidae), which comprises of 10-14 morphotypes that are distinguished solely by their distinct colour patterns, but which show little genetic differentiation. Our goal was to detect loci that show clear disequilibrium between morphotypes and across geographical locations. We conducted Amplified Fragment Length Polymorphism molecular analysis to quantify genetic differentiation among, and selection between, morphotypes. Three loci were consistently divergent beyond neutral expectations in repeated pair-wise morphotype comparisons using two different methods. These loci provide the first evidence for genes that may be associated with colour morphotype in the genus Hypoplectrus. DOI
99. Maljkovic, A; Côté, IM. (2011) Effects of tourism-related provisioning on the trophic signatures and movement patterns of an apex predator, the Caribbean reef shark.Biological Conservation 144 Effects of tourism-related provisioning on the trophic signatures and movement patterns of an apex predator, the Caribbean reef shark
Behavioural observations; Ecotourism; Non-consumptive exploitation; Shark conservation; Stable isotope analysis; Wildlife provisioning
Wildlife provisioning, i.e. the provision of bait to generate aggregations of charismatic megafauna as tourist attractions, occurs around the world. This practice is often promoted as an economic incentive to conserve the focal species, yet has stimulated debate based on the potential for risks to human safety and perceptions of behavioural shifts in provisioned populations. We studied a population of Caribbean reef sharks (Carcharhinus perezi) in the Bahamas that has been subject to regular provisioning for > 20 years. We used a combination of focal observations of sharks during feeding events, remote acoustic telemetry and stable isotope analysis of shark muscle tissue to determine the impacts of provisioning on the trophic signatures and ranging behaviour of sharks in this population. A small number of large sharks monopolised more than 50% of the bait on offer. These 'fed' individuals showed significant N-15 enrichment in their tissues compared to conspecifics of the same size that failed to obtain bait at the feeding site, and un-provisioned sharks from a control site. Despite the disparity in trophic signatures, fed, unfed and control sharks exhibited similar degrees of residency at their respective home receiver sites, and travelled similar daily minimum distances. Thus, despite long-term provisioning of this Caribbean reef shark population, there is no evidence for shifts in the behaviours considered which might affect the ecological role of these sharks. However, further research is required to examine potential indirect effects of shark provisioning on sympatric fauna and habitat before this activity can be placed within a sustainable marine conservation framework. (c) 2010 Elsevier Ltd. All rights reserved. DOI
98. Molloy, PP; Nyboer, EA; Côté, IM. (2011) Male-Male Competition in a Mixed-Mating Fish.Ethology 117: 586-596 Male-Male Competition in a Mixed-Mating Fish
Mating systems that comprise a mixture of pure males and self-fertilising hermaphrodites remain an evolutionary enigma. In particular, our understanding of the sexual selection pressures associated with such mating systems is nascent. Males can only reproduce by fertilising hermaphrodites' eggs, but hermaphrodites can also fertilise their own eggs and gain a genetic advantage by doing so. Consequently, there should be intense competition among males to access hermaphrodites. Here, we test the importance of male size, colour and heterozygosity in predicting the outcome of male-male competition using the mangrove rivulus, which has a male-hermaphrodite mixed-mating system. We pitted males against one another in dyadic laboratory trials to develop a dominance score for each male. We then correlated these scores with male length, several components of male colour, and heterozygosity. Male size was the only significant correlate of dominance: larger males dominated smaller males, implying selection for large male size. However, male mangrove rivulus are similar in size to hermaphrodites, indicating that directional selection for large body size in males is no greater than it is in hermaphrodites. Across all trials, colour was unrelated to dominance, but contests between similarly sized males were usually won by more colourful individuals. As mangrove rivulus are dichromatic, we suspect that male colour may prove to be more important in mate choice than we found it to be in intrasexual competition. Heterozygosity did not explain dominance directly, but correlated strongly with male size, implying an indirect role in intrasexual competition. DOI
97. Molloy, PP; Paddack, MJ; Reynolds, JD; Gage, MJG; Côté, IM. (2011) Relative size-at-sex-change in parrotfishes across the Caribbean: is there variance in a supposed life-history invariant?Evolutionary Ecology 25: 429-446 Relative size-at-sex-change in parrotfishes across the Caribbean: is there variance in a supposed life-history invariant?
Hermaphroditism; Invariant life-history analysis; Protandry; Protogyny; Sex allocation theory; Sex change
Invariant life-history theory has been used to identify parallels in life histories across diverse taxa. One important invariant life-history model predicts that, given simple assumptions and conditions, size-at-sex-change relative to maximum attainable body size (relative size-at-sex-change, RSSC) will be invariant across populations and species in sequential hermaphrodites. Even if there are broad species-wide limits to RSSC, populations could fine-tune RSSC to local conditions and, consequently, exhibit subtle but important differences in timing of sex change. Previous analyses of the invariant sex-change model have not explicitly considered the potential for meaningful differences in RSSC within the confines of a broader 'invariance'. Furthermore, these tests differ in their geographical and taxonomic scope, which could account for their conflicting conclusions. We test the model using several populations of three female-first sex-changing Caribbean parrotfish species. We first test for species-wide invariance using traditional log-log regressions and randomisation analyses of population-specific point estimates of RSSC. We then consider error around these point estimates, which is rarely incorporated into invariant analyses, to test for differences among populations in RSSC. Log-log regressions could not unequivocally diagnose invariance in RSSC across populations; randomisation tests identified an invariant RSSC in redband parrotfish only. Analyses that incorporated within-population variability in RSSC revealed differences among populations in timing of sex change, which were independent of geography for all species. While RSSC may be evolutionarily constrained (as in redband parrotfish), within these bounds the timing of sex change may vary among populations. This variability is overlooked by traditional invariant analyses and not predicted by the existing invariant model. DOI
96. Sutherland, WJ; Bardsley, S; Bennun, L; Clout, M; Côté, IM; Depledge, MH; Dicks, LV; Dobson, AP; Fellman, L; Fleishman, E; Gibbons, DW; Impey, AJ; Lawton, JH; Lickorish, F; Lindenmayer, DB; Lovejoy, TE; Mac Nally, R; Madgwick, J; Peck, LS; Pretty, J; Prior, SV; Redford, KH; Scharlemann, JPW; Spalding, M; Watkinson, AR. (2011) Horizon scan of global conservation issues for 2011.Trends in Ecology & Evolution 26 Horizon scan of global conservation issues for 2011
This review describes outcomes of a 2010 horizon-scanning exercise building upon the first exercise conducted in 2009. The aim of both horizon scans was to identify emerging issues that could have substantial impacts on the conservation of biological diversity, and to do so sufficiently early to encourage policy-relevant, practical research on those issues. Our group included professional horizon scanners and researchers affiliated with universities and non- and inter-governmental organizations, including specialists on topics such as invasive species, wildlife diseases and coral reefs. We identified 15 nascent issues, including new greenhouse gases, genetic techniques to eradicate mosquitoes, milk consumption in Asia and societal pessimism. DOI
94. Côté, IM; Maljkovic, A. (2010) Predation rates of Indo-Pacific lionfish on Bahamian coral reefs.Marine Ecology-Progress Series 404: 219-225 Predation rates of Indo-Pacific lionfish on Bahamian coral reefs
Behavioural observations; Biological invasions; Foraging strategies; Marine introductions; Predator-prey interactions; Turkeyfish
Indo-Pacific lionfish, mainly Pterois volitans, are currently invading coral reefs throughout the Caribbean region, where they have the potential to outcompete and prey upon a wide range of native reef animals. Here, we derive the first estimates of rates of predation by lionfish from field observations on natural reefs around New Providence, Bahamas. Although lionfish are reported to be crepuscular in their native range, they were very active during daylight hours. Lionfish were observed hunting at least 19 reef fish species, in at least 9 families. They hunted significantly more on overcast days and at greater depths, and frequently hunted near aggregations of fish at cleaning stations. Lionfish consumed native fish at an average rate of 1.44 kills h(-1) (0.29 kills h(-1) on clear days and 2.29 kills h(-1) on overcast days). This estimate may be conservative if lionfish hunt also between dusk and dawn. This rate is considerably higher than the only known prey consumption rate for P. volitans, which is extrapolated from ad libitum feeding of fish from the native range. Our results imply that using published predation rates from the native range to predict the impacts of lionfish on native Caribbean fish could lead to severe underestimation of these impacts. DOI
93. Darling, ES; McClanahan, TR; Côté, IM. (2010) Combined effects of two stressors on Kenyan coral reefs are additive or antagonistic, not synergistic.Conservation Letters 3: 122-130 Combined effects of two stressors on Kenyan coral reefs are additive or antagonistic, not synergistic
Climate change; fishing; coral reefs; ecological surprises; marine reserves; multiple stressors; interactive effects; synergy
A challenge for conservation science is predicting the impacts of co-occurring human activities on ecological systems. Multiple anthropogenic and natural stressors impact ecosystems globally and are expected to jeopardize their ecological functions and the success of conservation and management initiatives. The possibility that two or more stressors interact synergistically is of particular concern, but such nonadditive effects remain largely unidentified in nature. A long-term data set of hard coral cover from Kenyan reefs was used to examine the independent and interactive effects of two stressors: fishing and a temperature anomaly in 1998 that caused mass coral bleaching and mortality. While both stressors decreased coral cover, fishing by 51% and bleaching by 74%, they did not interact synergistically. Instead, their combined effect was antagonistic or weakly additive. The observed nonsynergistic response may be caused by the presence of one dominant stressor, bleaching, and cotolerance of coral taxa to both bleaching and fishing stressors. Consequently, coral bleaching has been the dominant driver of coral loss on Kenyan reefs and while marine reserves offer many benefits to reef ecosystems, they may not provide corals with a refuge from climate change. DOI
92. Favaro, B; Rutherford, DT; Duff, SD; Côté, IM. (2010) Bycatch of rockfish and other species in British Columbia spot prawn traps: Preliminary assessment using research traps.Fisheries Research 102: 199-206 Bycatch of rockfish and other species in British Columbia spot prawn traps: Preliminary assessment using research traps
echinoderm Rockfish; Bycatch; Sebastes; Trapping; Spot prawn; Pandalus platyceros
The spot prawn (Pandalus platyceros) trap fishery in British Columbia is endorsed by conservation organizations owing to the assumption of minimal bycatch. However, reported capture of juvenile rockfish (Sebastes spp.) in prawn traps has raised concern due to declines in abundance of many rockfish stocks. We document the bycatch observed in a 10-year (1999-2008) fishery-independent research survey that employed traps that are similar to the traps used in the commercial spot prawn fishery. Research traps produced 0.16-0.20 kg of non-target catch per kg of spot prawn catch, with bycatch consisting mainly of a variety of molluscs, non-target crustaceans, echinoderms, and fish. The overall rate of rockfish catch was low-0.015 rockfish per trap. The annual rate of rockfish bycatch has increased since 2004, to 0.039 rockfish per trap in 2008, while catch rates of other species have remained relatively constant. Our results confirm that spot prawn traps produce a low amount of bycatch by weight. However, they also suggest that rockfish mortality due to prawn trapping should be quantified in the commercial prawn fishery to determine how this source of mortality may affect rockfish stocks. Furthermore, research into bycatch reduction technology to improve trap selectivity, and thus reduce rockfish bycatch, would be desirable. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved. DOI
91. Holt, BG; Côté, IM; Emerson, BC. (2010) Signatures of speciation? Distribution and diversity of Hypoplectrus (Teleostei: Serranidae) colour morphotypes.Global Ecology and Biogeography 19: 432-441 Signatures of speciation? Distribution and diversity of Hypoplectrus (Teleostei: Serranidae) colour morphotypes
Caribbean; colour polymorphism; co-occurrence; coral reef; evolution; fish; hamlets; marine; sympatry
Aim To test historical and current influences on the distributions of sympatric colour morphotypes in the coral reef fish genus Hypoplectrus. Location The Caribbean and surrounding tropical waters. These areas cover the entire distribution of the genus. Methods A large and extensive database of Hypoplectrus sightings was used to establish the distribution of colour morphotypes and test a long-standing hypothesis regarding their origin. First, we considered the evidence for the previously proposed 'population centre' hypothesis, which suggests that current morphotype distributions reflect past conditions where these colour forms evolved in allopatry. Using morphotype sighting data, the existence of clusters in occurrence and density was tested. Second, we examined whether the observed patterns of morphotype co-occurrence deviate from random expectations using null model simulations, within subregions of the distribution of the genus, to infer ecological influences on distribution. Results There is considerable variation in morphotype distribution, with even widespread morphotypes showing geographical clustering. There is also little evidence to suggest past or current geographical isolation, with only one of the 11 morphotypes (Hypoplectrus chlorurus) showing a density distribution that is consistent with the population centre hypothesis. Null model analyses show that variation in local morphotype co-occurrence is typically significantly lower than expected under random dispersal conditions. Main conclusions Our results strongly suggest that morphotype co-occurrence is not random, but there is no evidence to suggest a past allopatric radiation in Hypoplectrus colour. Current distributions are likely to be driven by competitive interactions and/or habitat preferences. Our study highlights the value of the Hypoplectrus species complex as a system for the study of speciation in the marine environment, and implies that these closely related morphotypes have ecological relevance rather than being simple colour variants of a single polymorphic species. DOI
90. Mills, SC; Côté, IM. (2010) Crime and punishment in a roaming cleanerfish.Proceedings of the Royal Society B-Biological Sciences 277: 3617-3622 Crime and punishment in a roaming cleanerfish
conflict; cooperation; biological markets; cheating; partner switching; territory size
Cheating is common in cooperative interactions, but its occurrence can be controlled by various means ranging from rewarding cooperators to active punishment of cheaters. Punishment occurs in the mutualism involving the cleanerfish Labroides dimidiatus and its reef fish clients. When L. dimidiatus cheats, by taking scales and mucus rather than ectoparasites, wronged clients either chase or withhold further visits to the dishonest cleaner, which leads to more cooperative future interactions. Punishment of cheating L. dimidiatus may be effective largely because these cleaners are strictly site-attached, increasing the potential for repeated interactions between individual cleaners and clients. Here, we contrast the patterns of cheating and punishment in L. dimidiatus with its close relative, the less site-attached Labroides bicolor. Overall, L. bicolor had larger home ranges, cheated more often and, contrary to our prediction, were punished by cheated clients as frequently as, and not less often than, L. dimidiatus. However, adult L. bicolor, which had the largest home ranges, did not cheat more than younger conspecifics, suggesting that roaming, and hence the frequency of repeated interactions, has little influence on cheating and retaliation in cleaner-client relationships. We suggest that roaming cleaners offer the only option available to many site-attached reef fish seeking a cleaning service. This asymmetry in scope for partner choice encourages dishonesty by the partner with more options (i.e. L. bicolor), but to be cleaned by a cleaner that sometimes cheats may be a better option than not to be cleaned at all. DOI
89. Soares, MC; Côté, IM; Cardoso, SC; Oliveira, RF; Bshary, R. (2010) Caribbean Cleaning Gobies Prefer Client Ectoparasites Over Mucus.Ethology 116: 1244-1248 Caribbean Cleaning Gobies Prefer Client Ectoparasites Over Mucus
If cooperation often involves investment, then what specific conditions prevent selection from acting on cheaters that do not invest? The mutualism between the Indo-Pacific cleaner wrasse Labroides dimidiatus and its reef fish clients has been a model system to study conflicts of interest and their resolution. These cleaners prefer client mucus over ectoparasites - that is, they prefer to cheat - but punishment and partner switching by clients enforce cooperative behaviour by cleaners. By contrast, clients of Caribbean cleaning gobies (Elacatinus spp.) do not to use punishment or partner switching. Here, we test the hypothesis that the behavioural differences between these two cleaner fish systems are caused by differences in cleaner foraging preferences. In foraging choice experiments, we offered broadstripe cleaning gobies Elacatinus prochilos client-derived parasitic isopods, client mucus and a control food item. The cleaning gobies significantly preferred ectoparasites over mucus or the control item, which contrasts with cleaner wrasses. We propose that the low level of cleaner-client conflict arising from cleaning goby foraging preferences explains the observed lack of strategic partner control behaviour in the clients of cleaning gobies. DOI
88. Sutherland, WJ; Clout, M; Côté, IM; Daszak, P; Depledge, MH; Fellman, L; Fleishman, E; Garthwaite, R; Gibbons, DW; De Lurio, J; Impey, AJ; Lickorish, F; Lindenmayer, D; Madgwick, J; Margerison, C; Maynard, T; Peck, LS; Pretty, J; Prior, S; Redford, KH; Scharlemann, JPW; Spalding, M; Watkinson, AR. (2010) A horizon scan of global conservation issues for 2010.Trends in Ecology & Evolution 25: 1-7 A horizon scan of global conservation issues for 2010
Horizon scanning identifies emerging issues in a given field sufficiently early to conduct research to inform policy and practice. Our group of horizon scanners, including academics and researchers, convened to identify fifteen nascent issues that could affect the conservation of biological diversity. These include the impacts of and potential human responses to climate change, novel biological and digital technologies, novel pollutants and invasive species. We expect to repeat this process and collation annually. DOI
87. Uyarra, MC; Gill, JA; Côté, IM. (2010) Charging for Nature: Marine Park Fees and Management from a User Perspective.Ambio 39: 515-523 Charging for Nature: Marine Park Fees and Management from a User Perspective
Contingent valuation; Willingness-to-pay; Tourism; Marine protected areas; Bonaire; Caribbean
User fees can contribute to the financial sustainability of marine protected areas (MPAs), yet they must be acceptable to users. We explore changes in the fee system and management of Bonaire National Marine Park (BNMP) from the perspective of users. Responses from 393 tourists indicated that 90% were satisfied with park conditions and considered current user fees reasonable. However, only 47% of divers and 40% of non-divers were prepared to pay more. Diver willingness-to-pay (WTP) appears to have decreased since 1991, but this difference could be due in part to methodological differences between studies. Although current fees are close to diver maximum stated WTP, revenues could potentially be increased by improving the current fee system in ways that users deem acceptable. This potential surplus highlights the value of understanding user perceptions toward MPA fees and management. DOI
86. Alvarez-Filip, L; Dulvy, NK; Gill, JA; Côté, IM; Watkinson, AR. (2009) Flattening of Caribbean coral reefs: region-wide declines in architectural complexity.Proceedings of the Royal Society B-Biological Sciences 276: 3019-3025 Flattening of Caribbean coral reefs: region-wide declines in architectural complexity
HABITAT COMPLEXITY; FISH ASSEMBLAGES; CLIMATE-CHANGE; SEA-URCHIN; IMPACTS; ABUNDANCE; ECOSYSTEMS; HURRICANES; DIVERSITY; MORTALITY
Coral reefs are rich in biodiversity, in large part because their highly complex architecture provides shelter and resources for a wide range of organisms. Recent rapid declines in hard coral cover have occurred across the Caribbean region, but the concomitant consequences for reef architecture have not been quantified on a large scale to date. We provide, to our knowledge, the first region-wide analysis of changes in reef architectural complexity, using nearly 500 surveys across 200 reefs, between 1969 and 2008. The architectural complexity of Caribbean reefs has declined nonlinearly with the near disappearance of the most complex reefs over the last 40 years. The flattening of Caribbean reefs was apparent by the early 1980s, followed by a period of stasis between 1985 and 1998 and then a resumption of the decline in complexity to the present. Rates of loss are similar on shallow (<6 m), mid-water (6-20 m) and deep (>20 m) reefs and are consistent across all five subregions. The temporal pattern of declining architecture coincides with key events in recent Caribbean ecological history: the loss of structurally complex Acropora corals, the mass mortality of the grazing urchin Diadema antillarum and the 1998 El Nino Southern Oscillation-induced worldwide coral bleaching event. The consistently low estimates of current architectural complexity suggest regional-scale degradation and homogenization of reef structure. The widespread loss of architectural complexity is likely to have serious consequences for reef biodiversity, ecosystem functioning and associated environmental services. DOI
84. Côté, Isabelle M.; Paddack, Michelle J. (2009) 'Recycling' Data to Derive Environmental Indicators [Editorial].Environmental Bioindicators 4: 195-197 'Recycling' Data to Derive Environmental Indicators [Editorial]
When considering relatively short-term environmental bioindicators, most people think in terms of genetic or other markers, indicator species, and statistical evaluation of monitoring data. If long-term indicators are needed, then ice and sediment cores, tree rings and other natural records might come to mind. We suggest adding to both of these lists the huge, largely untapped reservoir of ecological information and documentation that lies dormant in filing cabinets, on dusty shelves and old computers around the world. Compilation of existing data ⎯ data recycling, if you will ⎯ can generate new indicators of environmental change, and also provide context for existing ones. DOI
82. Molloy, PP; McLean, IB; Côté, IM. (2009) Effects of marine reserve age on fish populations: a global meta-analysis.Journal of Applied Ecology 46: 743-751 Effects of marine reserve age on fish populations: a global meta-analysis
CORAL-REEF FISHES; PROTECTED AREAS; PALINURUS-ELEPHAS; GROWTH RATES; SIZE; RECRUITMENT; ASSEMBLAGES; SPILLOVER; RECOVERY; HABITAT
Marine reserves are widely used for conservation and fisheries management. However, there is debate surrounding the speed of population recovery inside reserves and how recovery differs among species. Here, we determine how reserve effectiveness in enhancing fish density changes with reserve age. We also examine how the effects of protection vary between fished and non-fished species and among species of different body sizes, which we use as a proxy for life history and ecology. We meta-analysed over 1000 ratios of fish densities (inside : outside reserves) taken from reserves of 1-26 years old from around the world. Overall, older reserves were more effective than younger reserves, with fish densities increasing within reserves by similar to 5% per annum relative to unprotected areas. Reserves older than 15 years consistently harboured more fish compared with unprotected areas; younger reserves were less reliably effective. Large, fished species responded strongly and positively to protection in old (> 15 years) and, unexpectedly, in new and young (< 10 years) reserves. Small, fished species and non-fished species of all sizes showed weaker responses to protection that did not vary predictably with reserve age. We expected large fish to respond more slowly to protection than smaller species. We also expected small species to decline after large fish had recovered (i.e. trophic cascades). Neither prediction was supported. Synthesis and applications. Our meta-analyses demonstrate that, globally, old reserves are more effective than young reserves at increasing fish densities. Our results imply that reserves should be maintained for up to 15 years following establishment, even if they initially appear ineffective. If protection is maintained for long enough, fish densities within reserves will recover and such benefits will be particularly pronounced for large, locally fished species. DOI
81. Molloy, PP; Reynolds, JD; Gage, MJG; Côté, IM. (2009) Effects of an artisanal fishery on non-spawning grouper populations.Marine Ecology-Progress Series 392: 253-262 Effects of an artisanal fishery on non-spawning grouper populations
IDEAL FREE DISTRIBUTION; US-VIRGIN-ISLANDS; SOUTHEASTERN UNITED-STATES; SEX-CHANGING FISH; GULF-OF-MEXICO; EPINEPHELUS-GUTTATUS; RED HIND; FLORIDA-KEYS; CORAL-REEF; SIZE DISTRIBUTION
Many populations of groupers (Teleostei: Serranidae) are overfished, partly because most species form spawning aggregations that are temporally and spatially predictable and therefore easily targeted by fisheries. However, most grouper fisheries operate year-round, thus there can also be high mortality during non-spawning periods. We investigated the impact of fishing around Anguilla, British West Indies, on a commercially important grouper, the red hind Epinephelus guttatus, during the non-breeding season. We combined information on the spatial intensity of the fishery with underwater surveys of groupers to test for associations between fishing intensity and fish size and density across 19 sites. Red hind density was unrelated to fishing intensity but red hinds were larger in areas that were targeted more intensively by fishers. While these results might be taken to suggest that fishing has no negative impacts on red hind demographics, we present evidence from fish markets that fishing intensity on this species during the non-spawning season is high. A variety of mechanisms may mask site-specific negative impacts on density and size of red hinds. In particular, fishers can easily move among sites to track grouper abundance and body size, thereby making it difficult to detect impacts on red hinds during the non-spawning season. DOI
80. Paddack, MJ; Reynolds, JD; Aguilar, C; Appeldoorn, RS; Beets, J; Burkett, EW; Chittaro, PM; Clarke, K; Esteves, R; Fonseca, AC; Forrester, GE; Friedlander, AM; Garcia-Sais, J; Gonzalez-Sanson, G; Jordan, LKB; McClellan, DB; Miller, MW; Molloy, PP; Mumby, PJ; Nagelkerken, I; Nemeth, M; Navas-Camacho, R; Pitt, J; Polunin, NVC; Reyes-Nivia, MC; Robertson, DR; Rodriguez-Ramirez, A; Salas, E; Smith, SR; Spieler, RE; Steele, MA; Williams, ID; Wormald, CL; Watkinson, AR; Côté, IM. (2009) Recent Region-wide Declines in Caribbean Reef Fish Abundance.Current Biology 19: 590-595 Recent Region-wide Declines in Caribbean Reef Fish Abundance
GREAT-BARRIER-REEF; MASS MORTALITY; CORAL-REEFS; DIADEMA-ANTILLARUM; TROPHIC CASCADES; MARINE RESERVES; PROTECTED AREAS; COMMUNITIES; POPULATIONS; ECOSYSTEMS
Profound ecological changes are occurring on coral reefs throughout the tropics [1-3], with marked coral cover losses and concomitant algal increases, particularly in the Caribbean region . Historical declines in the abundance of large Caribbean reef fishes likely reflect centuries of overexploitation [5-7]. However, effects of drastic recent degradation of reef habitats on reef fish assemblages have yet to be established. By using meta.-analysis, we analyzed time series of reef fish density obtained from 48 studies that include 318 reefs across the Caribbean and span the time period 1955-2007. Our analyses show that overall reef fish density has been declining significantly for more than a decade, at rates that are consistent across all subregions of the Caribbean basin (2.7% to 6.0% loss per year) and in three of six trophic groups. Changes in fish density over the past half-century are modest relative to concurrent changes in benthic cover on Caribbean reefs. However, the recent significant decline in overall fish abunclance and its consistency across several trophic groups. and among both fished and nonfished species indicate that Caribbean fishes have begun to respond negatively to habitat degradation. DOI
79. Soares, MC; Bshary, R; Côté, IM. (2009) Cleaning in pairs enhances honesty in male cleaning gobies.Behavioral Ecology 20: 1343-1347 Cleaning in pairs enhances honesty in male cleaning gobies
GOBIOSOMA-EVELYNAE; SERVICE QUALITY; PARTNER CONTROL; REEF FISH; GOBY; MUTUALISM; ECTOPARASITES; BEHAVIOR; MUCUS; DIET
A recent game theoretic model akin to an iterated prisoner's dilemma explored situations in which 2 individuals (the service providers) interact simultaneously with the same service recipient (the client). If providing a dishonest service pays, then each service provider may be tempted to cheat before its partner, even if cheating causes the client's departure; however, a theoretical cooperative solution also exists where both partners should reduce cheating rates. This prediction is supported by indirect measures of cheating (i.e., inferred from client responses) by pairs of Indo-Pacific bluestreak cleaner wrasses Labroides dimidiatus. Here, we examine how inspecting in pairs affects service quality in Caribbean cleaning gobies Elacatinus spp. We measured dishonesty directly by examining the stomach contents of solitary and paired individuals and calculating the ratio of scales to ectoparasites ingested. We found that the propensity to cheat of females and males differed: females always cleaned relatively honestly, whereas males cheated less when cleaning in pairs than when cleaning alone. However, overall, the cleaning service of single and paired individuals was similar. Our results confirm that cleaners cooperate when cleaning in pairs; however, our findings differ from the specific predictions of the model and the observations on L. dimidiatus. The differences may be due to differences in mating systems and cleaner-client interactions between the 2 cleaner fish species. DOI
78. Stewart, GB; Kaiser, MJ; Côté, IM; Halpern, BS; Lester, SE; Bayliss, HR; Pullin, AS. (2009) Temperate marine reserves: global ecological effects and guidelines for future networks.Conservation Letters 2: 243-253 Temperate marine reserves: global ecological effects and guidelines for future networks
Evidence-based conservation; marine protected areas; meta-analysis; no-take zones; systematic review
Marine reserves, areas closed to all fishing and other extractive activities, provide a refuge for species of commercial and conservation importance. Given the considerable resources committed to designing temperate reserve networks, we synthesized data from temperate reserves worldwide to determine their ecological effects. In common with other studies, we found higher density, biomass, and species richness in temperate marine reserves compared to adjacent exploited areas. However, there was considerable heterogeneity in magnitude of effect among reserves, variability which was largely unexplained by species or reserve characteristics. Our analytical approach allowed for formal power analyses, indicating that detection of large reserve effects in temperate systems globally requires monitoring at least 37 reserves. These results must be qualified by the limitations of data available and will undoubtedly vary at different spatio-temporal scales and for different focal species, but provide guidance for the design and monitoring of future marine conservations plans. International commitments toward establishment of multiple reserves offer a unique opportunity to assess reserve effectiveness; this opportunity can only be realized if reserves are designed to achieve clear and quantifiable objectives and are adequately monitored before and after establishment, based on appropriate power analyses, to assess how well those objectives are achieved. DOI
77. Sutherland, WJ; Adams, WM; Aronson, RB; Aveling, R; Blackburn, TM; Broad, S; Ceballos, G; Côté, IM; Cowling, RM; Da Fonseca, GAB; Dinerstein, E; Ferraro, PJ; Fleishman, E; Gascon, C; Hunter, M; Hutton, J; Kareiva, P; Kuria, A; MacDonald, DW; MacKinnon, K; Madgwick, FJ; Mascia, MB; McNeely, J; Milner-Gulland, EJ; Moon, S; Morley, CG; Nelson, S; Osborn, D; Pai, M; Parsons, ECM; Peck, LS; Possingham, H; Prior, SV; Pullin, AS; Rands, MRW; Ranganathan, J; Redford, KH; Rodriguez, JP; Seymour, F; Sobel, J; Sodhi, NS; Stott, A; Vance-Borland, K; Watkinson, AR. (2009) One Hundred Questions of Importance to the Conservation of Global Biological Diversity.Conservation Biology 23: 557-567 One Hundred Questions of Importance to the Conservation of Global Biological Diversity
CLIMATE-CHANGE; IMPLEMENTATION; SCIENCE; TRENDS; UK
We identified 100 scientific questions that, if answered, would have the greatest impact on conservation practice and policy. Representatives from 21 international organizations, regional sections and working groups of the Society for Conservation Biology, and 12 academics, from all continents except Antarctica, compiled 2291 questions of relevance to conservation of biological diversity worldwide. The questions were gathered from 761 individuals through workshops, email requests, and discussions. Voting by email to short-list questions, followed by a 2-day workshop, was used to derive the final list of 100 questions. Most of the final questions were derived through a process of modification and combination as the workshop progressed. The questions are divided into 12 sections: ecosystem functions and services, climate change, technological change, protected areas, ecosystem management and restoration, terrestrial ecosystems, marine ecosystems, freshwater ecosystems, species management, organizational systems and processes, societal context and change, and impacts of conservation interventions. We anticipate that these questions will help identify new directions for researchers and assist funders in directing funds. DOI
76. Uyarra, M; Watkinson, A; Côté, IM. (2009) Managing Dive Tourism for the Sustainable Use of Coral Reefs: Validating Diver Perceptions of Attractive Site Features.Environmental Management 43: 1-16 Managing Dive Tourism for the Sustainable Use of Coral Reefs: Validating Diver Perceptions of Attractive Site Features
VISITOR PERCEPTIONS; CAMPSITE IMPACTS; PROTECTED AREAS; CARIBBEAN CORAL; DIVING IMPACTS; CLIMATE-CHANGE; MARINE PARKS; ISLAND; COMMUNITIES; RECREATION
It has been argued that strategies to manage natural areas important for tourism and recreation should integrate an understanding of tourist preferences for specific natural features. However, the accuracy of tourist recalled perceptions of environmental attributes, which are usually derived from post hoc surveys and used to establish management priorities, is currently unmeasured. We tested the validity of the relationship between tourist-stated preferences and actual condition of coral reefs around the Caribbean island of Bonaire. Using standardized questionnaires, we asked 200 divers to select their most and least favorite dive sites and the attributes that contributed to that selection. We also carried out ecological surveys at 76 of the 81 dives sites around the island to assess the actual conditions of the attributes indicated as important for site selection. Fish- and coral-related attributes were key features affecting dive enjoyment. In general, divers appeared to be able to perceive differences between sites in the true condition of biological attributes such as fish species richness, total number of fish schools, live coral cover, coral species richness, and reef structural complexity, although men and women divers differed in their ability to perceive/recall some of the attributes. Perceived differences in environmental attributes, such as surface conditions, underwater current, and the likelihood of encountering rare fish and sea turtles, were not empirically validated. The fact that divers perceive correctly differences in the condition of some of the key biological attributes that affect dive enjoyment reinforces the need to maintain overall reef condition at satisfactory levels. However, variation in accuracy of perceptions owing to demographic factors and attribute type suggests the need for caution when using public perceptions to develop environmental management strategies, particularly for coral reefs. DOI
75. Darling, ES; Côté, IM. (2008) Quantifying the evidence for ecological synergies.Ecology Letters 11: 1278-1286 Quantifying the evidence for ecological synergies
meta-analysis, mortality, multiple stressors, non-additive effects, synergy.
There is increasing concern that multiple drivers of ecological change will interact synergistically to accelerate biodiversity loss. However, the prevalence and magnitude of these interactions remain one of the largest uncertainties in projections of future ecological change. We address this uncertainty by performing a meta-analysis of 112 published factorial experiments that evaluated the impacts of multiple stressors on animal mortality in freshwater, marine and terrestrial communities. We found that, on average, mortalities from the combined action of two stressors were not synergistic and this result was consistent across studies investigating different stressors, study organisms and life-history stages. Furthermore, only one-third of relevant experiments displayed truly synergistic effects, which does not support the prevailing ecological paradigm that synergies are rampant. However, in more than three-quarters of relevant experiments, the outcome of multiple stressor interactions was non-additive (i.e. synergies or antagonisms), suggesting that ecological surprises may be more common than simple additive effects.PDF DOI
74. Fish, MR; Côté, IM; Horrocks, JA; Mulligan, B; Watkinson, AR; Jones, AP. (2008) Construction setback regulations and sea-level rise: Mitigating sea turtle nesting beach loss.Ocean & Coastal Management 51: 330-341 Construction setback regulations and sea-level rise: Mitigating sea turtle nesting beach loss
Global sea-level rise of up to 0.6 m is predicted in the next 100 years. In areas where coastal structures prevent landward migration of beaches, a major impact of sea-level rise will be a loss of beach habitat, with repercussions for beach-dependent organisms such as sea turtles. Setback regulations, which prohibit construction within a set distance from the sea, have the potential to mitigate loss of beach area by providing a buffer zone which allows for the natural movement of beaches in response to perturbation. The potential impact of a rise in sea level on 11 important sea turtle nesting beaches in Barbados under a range of setback regulations was determined. Three sea-level rise scenarios were modelled under five different setback regulations (10, 30, 50, 70 and 90 m). Beach area was lost from all beaches under all sea-level rise scenarios with a 10 and 30 m setback, from some beaches with a 50 m setback and from one beach with a 70 m setback. No beach area was lost with a 90 m setback distance. Sea turtles nest within a range of beach elevations and there was an overall loss of beach habitat within the preferred nesting elevation range with both a 10 and 30 m setback under all sea-level rise scenarios. Considerable variation in the extent of beach and nesting area loss was observed. The implementation and enforcement of adequate setback regulations have the potential to maintain the ecological and economic function of beaches in the face of extensive coastal development and sea-level rise. (C) 2007 Elsevier Ltd. All rights reserved. DOI
73. Holt, BG; Emerson, BC; Newton, J; Gage, MJG; Côté, IM. (2008) Stable isotope analysis of the Hypoplectrus species complex reveals no evidence for dietary niche divergence.Marine Ecology-Progress Series 357: 283-289 Stable isotope analysis of the Hypoplectrus species complex reveals no evidence for dietary niche divergence
Caribbean; dietary niche; hamlets; marine adaptive radiation; colour polymorphism
The polymorphic coral reef fish genus Hypoplectrus (hamlets) provides an excellent system for examining the initial stages of natural biological divergence in the expansive marine environment. Despite close genetic similarities, hamlets occur in assortatively mating colour morphotypes. In this study, we determined whether ecological differences exist between morphs that could reinforce the assortative mating pattern within morphs. We compared the carbon and nitrogen stable isotope dietary signatures of 6 hamlet morphotypes from 5 geographically distant locations. Across 364 individuals, and with the exception of fish sampled in the Gulf of Mexico, no significant isotopic associations with morphotype were detected. Our results therefore provide no evidence that different hamlet morphs are associated with distinct dietary niches, despite finding highly significant geographical differentiation for both isotopes. We argue that tight assortative mating without ecological divergence could be maintained through the demands of reciprocal cooperation within a reproductive pattern of simultaneous hermaphroditism which characterises all hamlets. DOI
72. Lengkeek, W; Didderen, K; Côté, IM; van der Zee, EM; Snoek, RC; Reynolds, JD. (2008) Plasticity in sexual size dimorphism and Rensch's rule in Mediterranean blennies (Blenniidae).Canadian Journal of Zoology-Revue Canadienne de Zoologie 86: 1173-1178 Plasticity in sexual size dimorphism and Rensch's rule in Mediterranean blennies (Blenniidae)
Comparative analyses of sexual size dimorphism (SSD) across species have led to the discovery of Rensch's rule. This rule states that SSD increases with body size when males are the largest sex, but decreases with increasing size when females are larger. Within-species comparisons of SSD in fish are rare, yet these may be a valuable tool to investigate evolutionary patterns on a fine scale. This study compares SSD among closely related populations of three species of Mediterranean blennies (Blenniidae): Microlipophrys canevae (Vinciguerra, 1880), Parablennius incognitus (Bath 1968), and Aidablennius sphynx (Valenciennes, 1836). SSD varied more among populations than among species and Rensch's rule was confirmed within two species. It is not likely that the variation among populations in SSD mirrors genetic variation, as many of the populations were in close proximity of one another, with a high potential for genetic exchange. This study complements larger scale analyses of other taxa and demonstrates the fine scale on which evolutionary processes responsible for Rensch's rule may be operating. DOI
71. Molloy, PP; Reynolds, JD; Gage, MJG; Mosqueirac, L; Côté, IM. (2008) Links between sex change and fish densities in marine protected areas.Biological Conservation 141: 187-197 Links between sex change and fish densities in marine protected areas
body size; exploitation; fishing; grouper; hermaphroditism; meta-analysis; parrotfish
Sex change is widespread among marine fishes, including many species that are fished heavily, and is thought to be of conservation concern under some circumstances. As such, an important question in conservation is whether the implementation of marine protected areas (MPAs), which is a commonly used marine conservation tool, works as effectively for sex-changers as for non-sex-changers. To address this issue, we used meta-analyses of the ratio of fish abundances inside vs. outside MPAs to determine whether sex change affects the extent to which fish densities respond to protection. When all data were considered, there were similar responses to protection irrespective of reproductive mode. However, when analyses were restricted to older reserves (at least 10 years' protection), female-first sex-changers consistently benefited from protection, Non-sex-changers and male-first sex-changers showed more variable responses to protection and, as a result, there were no significant differences between fish with different reproductive modes in their overall response to protection. The same results were observed when the effects of fisheries status (targeted vs. not targeted) were controlled. Our results support the use of MPAs as important components of conservation and demonstrate that old reserves are most consistently beneficial to female-first sex-changing species. Finally, our results highlight the fact that some effects of protection are only detectable after several generations. (c) 2007 Elsevier Ltd. All rights reserved. DOI
70. Soares, MC; Bshary, R; Cardoso, SC; Côté, IM. (2008) Does competition for clients increase service quality in cleaning gobies?Ethology 114: 625-632 Does competition for clients increase service quality in cleaning gobies?
In a biological market, members of one trading class try to outbid each other to gain access to the most valuable partners. Competition within class can thus force individuals to trade goods or services more cheaply, ultimately resulting in conflict (e.g. cheating) over the value of commodities. Cleaning symbioses among fish appear to be good examples of biological markets. However, the existence and effect of outbidding competition among either types of traders (cleaners or clients) have never been tested. We examined whether increasing competition among cleaning gobies (Elacatinus spp.) for access to clients results in outbidding in the form of provision of a better cleaning service. On reefs where fish clients visited cleaning stations less frequently, and thus competition among cleaners was higher, cleaning gobies ingested fewer scales relative to the number of ingested parasites, i.e. they cleaned more honestly. This shift in cleaner behaviour towards greater honesty is consistent with a greater market value of access to clients in the face of competition among cleaners. However, this pattern could have also arisen as a result of differences in ectoparasite availability across reefs and therefore in value of the commodity offered by clients. Experimental manipulations will be required to determine whether cleaning service quality by cleaning gobies was enhanced solely because of competitive outbidding. DOI
69. Soares, MC; Bshary, R; Cardoso, SC; Côté, IM. (2008) The meaning of jolts by fish clients of cleaning gobies.Ethology 114: 209-214 The meaning of jolts by fish clients of cleaning gobies
Cooperative interactions offer the inherent possibility of cheating by each of the interacting partners. A key challenge to behavioural observers is to recognize these conflicts, and find means to measure reliably cheating in natural interactions. Cleanerfish Labroides dimidiatus cheat by taking scales and mucus from their fish clients and such dishonest cleaning has been previously recognized in the form of whole-body jolts by clients in response to cleaner mouth contact. In this study, we test whether jolts may be a general client response to cheating by cleaners. We experimentally varied the ectoparasite loads of yellowtail damselfish (Microspathodon chrysurus), a common client of the cleaning goby Elacantinus evelynae, and compared the rates of jolts on parasitized and deparasitized clients. As predicted if jolts represent cleaner cheating, deparasitized clients jolted more often than parasitized clients, and overall jolt rates increased over time as client parasite load was presumably reduced by cleaning activity. Yellowtail damselfish in the wild jolted significantly less frequently than those in captivity, which is consistent with a loss of ectoparasites during capture. Our results suggest that jolts by clients of cleaning gobies are not related to the removal of ectoparasites. Client jolts may therefore be a generally accurate measure of cheating by cleanerfish. DOI
68. Soares, MC; Bshary, R; Côté, IM. (2008) Does cleanerfish service quality depend on client value or choice options?Animal Behaviour 76: 123-130 Does cleanerfish service quality depend on client value or choice options?
biological market; bluestreak cleaner wrasse; cleaning fish mutualism; client choice options verses value; gnathiid availability; inspection duration; Labroides dimidiatus
Cleaning fish mutualisms appear to be good examples of biological markets. Two classes of traders exist: cleaner fish and their fish clients, each of which supplies a commodity required by the other (ectoparasite removal and a meal, respectively). However, clients are not all treated similarly by cleaners. There is evidence that clients with choice options (with potential access to more than one cleaner) have priority of access over clients without choice options. Market theory predicts that client value (i.e. ectoparasite load) should also influence cleaning service quality. We examined the relative roles of client choice options and client value in determining the duration of cleaning interactions between bluestreak cleaner wrasse, Labroides dimidiatus, and their clients across three geographically distant sites. We found a lack of covariation between client choice options and gnathiid ectoparasite loads. Geographical differences in gnathiid availability altered the importance of client gnathiid load as a determinant of client inspection duration. As predicted, clients with both choice options and high gnathiid loads were inspected for longer, but this was observed only in an area with a relatively high incidence of parasitism. These correlational results suggest that the importance of client choice for aspects of cleaner fish service quality may be modulated by parasite availability. (C) 2008 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved. DOI
67. Soares, MC; Côté, IM; Cardoso, SC; Bshary, R. (2008) The cleaning goby mutualism: a system without punishment, partner switching or tactile stimulation.Journal of Zoology 276: 306-312 The cleaning goby mutualism: a system without punishment, partner switching or tactile stimulation
In the cleanerfish-client mutualism involving the Indo-Pacific cleaner wrasse Labroides dimidiatus and its reef fish clients, mechanisms such as 'tactile stimulation', partner switching and punishment are used by clients to control cheating by cleaners. We sought to establish whether these behaviours are general features of cleaning mutualisms by examining their presence in interactions between Caribbean cleaning gobies (Elacatinus spp.) and their clients. The cleaning goby-client mutualism bears several similarities to the cleaner wrasse system: clients visit cleaners frequently to have their ectoparasites removed while cleaners depend heavily on these visits for food, and cheating by cleaning gobies is also prevalent. However, our data revealed striking differences between the two cleanerfish systems: clients did not seem to attempt to control cheating by cleaning gobies and cleaning gobies did not perform tactile stimulation on their clients. We suggest three hypotheses that might explain these major differences between both systems, based on differences in mutual dependence between cleaners and clients or cognitive ability of cleaners, differences in costs of being cheated and differences in foraging preferences by cleaners. Interactions between L. dimidiatus and its clients should probably not be seen as the 'standard' marine fish cleaning mutualism. DOI
65. Cheney, KL; Côté, IM. (2007) Aggressive mimics profit from a model-signal receiver mutualism.Proceedings of the Royal Society B-Biological Sciences 274: 2087-2091 Aggressive mimics profit from a model-signal receiver mutualism
aggressive mimicry; coral reef fish; cleaner wrasse; cleaning symbioses
Mimetic species have evolved to resemble other species to avoid predation (protective mimicry) or gain access to food (aggressive mimicry). Mimicry systems are frequently tripartite interactions involving a mimic, model and 'signal receiver'. Changes in the strength of the relationship between model and signal receiver, owing to shifting environmental conditions, for example, can affect the success of mimics in protective mimicry systems. Here, we show that an experimentally induced shift in the strength of the relationship between a model (bluestreak cleaner fish, Labroides dimidiatus) and a signal receiver (staghorn damselfish, Amblyglyphidodon curacao) resulted in increased foraging success for an aggressive mimic (bluestriped fangblenny, Plagiotremus rhinorhynchos). When the parasite loads of staghorn damselfish clients were experimentally increased, the attack success of bluestriped fangblenny on damselfish also increased. Enhanced mimic success appeared to be due to relaxation of vigilance by parasitized clients, which sought cleaners more eagerly and had lower overall aggression levels. Signal receivers may therefore be more tolerant of and/or more vulnerable to attacks from aggressive mimics when the net benefit of interacting with their models is high. Changes in environmental conditions that cause shifts in the net benefits accrued by models and signal receivers may have important implications for the persistence of aggressive mimicry systems. DOI
64. Côté, IM; Cheney, KL. (2007) A protective function for aggressive mimicry?Proceedings of the Royal Society B-Biological Sciences 274: 2445-2448 A protective function for aggressive mimicry?
coral reef fish; Labroides dimidiatus; mimicry; Plagiotremus tapeinosoma; Plagiotremus rhinorhynchos
Mimicry often involves a protective element, whereby the risk of predation on mimics is reduced owing to their resemblance to unpalatable models. However, protection from predation has so far seemed unimportant in aggressive mimicry, where mimics are usually predators rather than prey. Here, we demonstrate that bluestriped fangblennies (Plagiotremus rhinorhynchos), which are aggressive mimics of juvenile bluestreak cleaner wrasse (Labroides dimidiatus), derive significant protection benefits from their resemblance to cleaner fish. Field observations revealed that mimetic fangblennies were chased by potential victims less often than individuals of a closely related, ecologically and behaviourally similar but non- mimetic species (Plagiotremus tapeinosoma). After attacks, proximity to models protected mimics from retaliation by victims, but the effect of colour similarity was less clear. Both colour resemblance and physical proximity to models thus appear to protect cleaner- fish mimics from aggression by potential and actual victims of their attacks. Our results suggest that the mimicry types observed in nature, which are usually distinguished on the basis of the benefits accrued to mimics, may in fact overlap greatly in the benefits provided. DOI
63. Molloy, PP; Goodwin, NB; Côté, IM; Gage, MJG; Reynolds, JD. (2007) Predicting the effects of exploitation on male-first sex-changing fish.Animal Conservation 10: 30-38 Predicting the effects of exploitation on male-first sex-changing fish
barramundi; fisheries model; fishing; hermaphroditism; protandry; protogyny; shrimp
Sex change is widespread among tropical marine fishes, many of which are targeted by fisheries. Conservation concerns have been raised that sex-changing species may be particularly prone to overexploitation by size-selective fishing. In the case of male-first sex-changers, populations may become egg limited if large females are disproportionately killed. However, if males reduce the size at which they change sex in response to higher female mortality, the population may still be sufficiently productive. We develop an age-based model to explore the effects of fishing on two types of male-first sex-changing fish: one with flexibility in size-at-sex-change and one without. These effects were compared with those of non-sex-changing populations with similar life-history and population characteristics. The model predicts that if male-first sex-changers cannot respond to elevated female mortality by adjusting their size-at-sex-change, the population will be more prone to recruitment limitation and extinction than non-sex-changers. These effects will be amplified as smaller individuals become susceptible to fishing mortality. However, if size-at-sex-change is flexible, sex-changers may be as resilient to fishing as non-sex-changers. Knowledge of a species' size-at-sex-change, and the mechanisms controlling it, should be fundamental to the selection of fisheries conservation strategies.PDF DOI
62. Molloy, PP; Goodwin, NB; Côté, IM; Reynolds, JD; Gage, MJG. (2007) Sperm competition and sex change: A comparative analysis across fishes.Evolution 61: 640-652 Sperm competition and sex change: A comparative analysis across fishes
hermaphrodite; mating system; protogyny; reproductive model; sex allocation theory; size-advantage model; Teleostei
Current theory to explain the adaptive significance of sex change over gonochorism predicts that female-first sex change could be adaptive when relative reproductive success increases at a faster rate with body size for males than for females. A faster rate of reproductive gain with body size can occur if larger males are more effective in controlling females and excluding competitors from fertilizations. The most simple consequence of this theoretical scenario, based on sexual allocation theory, is that natural breeding sex ratios are expected to be female biased in female-first sex changers, because average male fecundity will exceed that of females. A second prediction is that the intensity of sperm competition is expected to be lower in female-first sex-changing species because larger males should be able to more completely monopolize females and therefore reduce male-male competition during spawning. Relative testis size has been shown to be an indicator of the level of sperm competition, so we use this metric to examine evolutionary responses to selection from postcopulatory male-male competition. We used data from 116 comparable female-first sex-changing and nonhermaphroditic (gonochoristic) fish species to test these two predictions. In addition to cross-species analyses we also controlled for potential phylogenetic nonindependence by analyzing independent contrasts. As expected, breeding sex ratios were significantly more female biased in female-first sex-changing than nonhermaphroditic taxa. In addition, males in female-first sex changers had significantly smaller relative testis sizes that were one-fifth the size of those of nonhermaphroditic species, revealing a new evolutionary correlate of female-first sex change. These results, which are based on data from a wide range of taxa and across the same body-size range for either mode of reproduction, provide direct empirical support for current evolutionary theories regarding the benefits of female-first sex change. DOI
61. Newton, K; Côté, IM; Pilling, GM; Jennings, S; Dulvy, NK. (2007) Current and future sustainability of island coral reef fisheries.Current Biology 17: 655-658 Current and future sustainability of island coral reef fisheries
Overexploitation is one of the principal threats to coral reef diversity, structure, function, and resilience [1, 2]. Although it is generally held that coral reef fisheries are unsustainable [3-5], little is known of the overall scale of exploitation or which reefs are overfished . Here, on the basis of ecological footprints and a review of exploitation status [7, 8], we report widespread unsustainability of island coral reef fisheries. Over half (55%) of the 49 island countries considered are exploiting their coral reef fisheries in an unsustainable way. We estimate that total landings of coral reef fisheries are currently 64% higher than can be sustained. Consequently, the area of coral reef appropriated by fisheries exceeds the available effective area by similar to 75,000 km(2), or 3.7 times the area of Australia's Great Barrier Reef, and an extra 196,000 km(2) of coral reef may be required by 2050 to support the anticipated growth in human populations. The large overall imbalance between current and sustainable catches implies that management methods to reduce social and economic dependence on reef fisheries are essential to prevent the collapse of coral reef ecosystems while sustaining the well-being of burgeoning coastal populations. DOI
60. Soares, MC; Cardoso, SC; Côté, IM. (2007) Client preferences by Caribbean cleaning gobies: food, safety or something else?Behavioral Ecology and Sociobiology 61: 1015-1022 Client preferences by Caribbean cleaning gobies: food, safety or something else?
cleaning symbiosis; Elacatinus spp; ectoparasites; food-safety trade-off; foraging preferences; predation risk
Predation risk is amongst the most pervasive selective pressures influencing behaviour and animals have been repeatedly shown to trade-off foraging success for safety. We examined the nature of this trade-off in cleaning symbioses amongst Caribbean coral reef fishes. We predicted that cleaning gobies (Elacatinus evelynae and Elacatinus prochilos) should prefer fish clients that pose a low risk of predation (e.g. herbivores) over clients that may have more ectoparasites but pose a higher risk (e.g. piscivores). Our field observations revealed that cleaners did clean preferentially client species with more parasites but predatory and non-predatory clients had similar ectoparasite loads. Despite the lack of a foraging advantage for inspecting predators, cleaners did not avoid risky clients. On the contrary, a larger proportion of visiting predators than non-predators was inspected, gobies initiated more interactions with predatory clients, and predators were attended to immediately upon arrival at cleaning stations. This preferential treatment of dangerous clients may allow the rapid identification of cleaners as non-prey item or may be due to the effect of predators on the rest of the cleaners' clientele, which avoided cleaning stations whilst predators were present. Dealing with potentially risky clients may allow gobies to regain access to their main food source: non-predatory clients. DOI
59. Uyarra, MC; Côté, IM. (2007) The quest for cryptic creatures: Impacts of species-focused recreational diving on corals.Biological Conservation 136: 77-84 The quest for cryptic creatures: Impacts of species-focused recreational diving on corals
coral reef management; diving; frogfish; recreational damage; seahorse
Coral reefs are popular with ecotourists, but the impact of divers on reefs is cause for concern. In this study, we assessed the damage to corals caused by divers seeking cryptic but charismatic fish such as seahorses (family Syngnathidae) and frogfishes (Antennariidae), which are found on reefs around the world. These fish are closely associated with the reef substratum, thus bringing divers into close proximity to coral. We found that when in the vicinity of frogfish and seahorses, divers made unintentional contact with corals significantly more often and for longer periods than when these species were absent. This change in diver behaviour resulted in a greater frequency of coral breakage and scarring at seahorse/frogfish sites than at ecologically equivalent control sites. However, the spatial extent of damage appeared limited. Beyond 1-3 m from the seahorse or frogfish, coral breakage and scarring rate decreased to levels similar to those of control sites. None of the coral species, which suffered the most damage, was particularly rare, suggesting that the habitat conservation concern of these marked shifts in diver behaviour is limited. Nevertheless, the use of pre-dive briefings and smaller dive group sizes could minimise the damage caused by divers approaching cryptic species of interest near the reef. (C) 2006 Elsevier Ltd. All rights reserved. DOI
58. Whiteman, EA; Côté, IM; Reynolds, JD. (2007) Ecological differences between hamlet (Hypoplectrus : Serranidae) colour morphs: between-morph variation in diet.Journal of Fish Biology 71: 235-244 Ecological differences between hamlet (Hypoplectrus : Serranidae) colour morphs: between-morph variation in diet
ecological specialization; morpho-species; niche partitioning; speciation; sympatry
Dietary differences between hamlet Hypoplectrus spp. colour morphs were examined in fishes from Puerto Rico, U.S. Virgin Islands, Curacao, Honduras and Belize. Hamlet diet across all countries was characterized by large overlap between most colour morphs in both the proportion and numbers of dietary items consumed, although some differences between morphs were apparent. Indigo hamlets Hypoplectrus indigo were the only morph to consume fishes (blue chromis Chromis cyanea and sunshinefish Chromis insolata) almost exclusively. The sympatric occurrence of other ecologically indistinguishable colour morphs, however, suggests that divergent ecological selection alone cannot explain population divergence in hamlets. Geographical variation in diet was also observed within black Hypoplectrus nigricans and yellowtail Hypoplectrus chlorurus hamlets which may reflect geographical differences in prey availability or differences in prey choice. (c) 2007 The Authors Journal compilation. (c) 2007 The Fisheries Society of the British Isles.PDF DOI
57. Wynne, SP; Côté, IM. (2007) Effects of habitat quality and fishing on Caribbean spotted spiny lobster populations.Journal of Applied Ecology 44: 488-494 Effects of habitat quality and fishing on Caribbean spotted spiny lobster populations
coral reefs; Guinea chick lobster; habitat quality; lobster distribution; marine protected areas; no-take areas; sustainable exploitation
1. Overfishing has had detrimental impacts on many marine populations. However, measurements of the effect of exploitation are often confounded by intersite differences in habitat quality. 2. To assess the effects of fishing and habitat quality on spotted spiny lobster Panulirus guttatus, the target of a luxury fishery in the Caribbean, lobster populations were assessed on 12 reefs around Anguilla, British West Indies. Habitat quality was measured by the availability of foraging habitat. Fishing intensity was estimated through interviews with fishers. 3. Spotted spiny lobster densities were significantly higher on reefs with good-quality habitat than on poorer-quality reefs. However, mean lobster size remained constant regardless of habitat quality. 4. In contrast, lobsters were on average smaller in heavily fished than in unfished areas because of the removal of the largest size classes by fishers. Changes in densities as a result of fishing could not be detected, and there was no interaction between fishing pressure and habitat quality. 5. The lack of an observable effect of fishing on lobster population densities may be because fishers more intensively target high-quality habitats. Fishing has probably reduced lobster densities on high-quality reefs to a greater extent than on low-quality reefs, but the high productivity of good-quality sites is still sustaining more intense fishing. 6. Synthesis and applications. The importance of habitat quality in sustaining P. guttatus populations in the face of intense exploitation suggests that management efforts should be aimed at enhancing reef health. The latter may be achieved through the establishment of no-take areas on good-quality reefs. Such actions should, however, be expected to generate conflicts with stakeholders because these reefs are currently those most heavily exploited. DOI
56. Culling, MA; Janko, K; Boron, A; Vasil'Ev, VP; Côté, IM; Hewitt, GM. (2006) European colonization by the spined loach (Cobitis taenia) from Ponto-Caspian refugia based on mitochondrial DNA variation.Molecular Ecology 15: 173-190 European colonization by the spined loach (Cobitis taenia) from Ponto-Caspian refugia based on mitochondrial DNA variation
colonization; glacial refugia; mitochondrial DNA; nested clade phylogeographical analysis; Pleistocene
In the last 20 years, new species, asexual reproduction, polyploidy and hybridization have all been reported within the genus Cobitis. An understanding of the current distribution and baseline phylogeographical history of 'true' nonhybrid Cobitis species is crucial in order to unravel these discoveries. In the present work, we investigated the phylogeography of the spined loach, Cobitis taenia, using 1126 bp of the mitochondrial cytochrome b gene from 174 individuals collected at 47 sites. In total, 51 haplotypes that differed at 49 positions (4.35%) were detected. We deduce that C. taenia survived European glaciations in at least three refuges in the Ponto-Caspian area. Two of these refuges each provided a major lineage that recolonized Europe in separate directions: one westward to England and the other spreading north into Russia before moving west. A third (minor) lineage that contributed little to the recolonization of Europe was also revealed - remaining near its Black Sea refuge. However, more recent history was difficult to resolve with colonization from a more western refugium during the last glacial maximum (LGM) a distinct possibility. Nested clade analysis indicates a pattern of restricted gene flow with isolation by distance at the first two levels and overall. Unlike many other European freshwater fish species, the Danube is not part of the current distribution of C. taenia, nor was it used as either a refuge or a source of colonization of Europe. Low genetic diversity within C. taenia suggests that its colonization of Europe is relatively recent. Demographic analyses revealed a history of recent expansion and isolation by distance. DOI
55. Gill, JA; Watkinson, AR; McWilliams, JP; Côté, IM. (2006) Opposing forces of aerosol cooling and El Nino drive coral bleaching on Caribbean reefs.Proceedings of the National Academy of Sciences of the United States of America 103: 18870-18873 Opposing forces of aerosol cooling and El Nino drive coral bleaching on Caribbean reefs
climate change; coral reef; habitat degradation; volcanoes
Bleaching of corals as a result of elevated sea surface temperatures (SST) is rapidly becoming a primary source of stress for reefs globally; the scale and extent of this threat will depend on how the drivers of SST interact to influence bleaching patterns. We demonstrate how the opposing forces of the El Nino-Southern Oscillation (ENSO) and levels of atmospheric aerosols drive regional-scale patterns of coral bleaching across the Caribbean. When aerosol levels are low, bleaching is largely determined by El Nino strength, but high aerosol levels mitigate the effects of a severe El Nino. High aerosol levels, resulting principally from recent volcanic activity, have thus protected Caribbean reefs from more frequent widespread bleaching events but cannot be relied on to provide similar protection in the future. DOI
53. Balmford, A; Bennun, L; ten Brink, B; Cooper, D; Côté, IM; Crane, P; Dobson, A; Dudley, N; Dutton, I; Green, RE; Gregory, RD; Harrison, J; Kennedy, ET; Kremen, C; Leader-Williams, N; Lovejoy, TE; Mace, G; May, R; Mayaux, P; Morling, P; Phillips, J; Redford, K; Ricketts, TH; Rodriguez, JP; Sanjayan, M; Schei, PJ; van Jaarsveld, AS; Walther, BA. (2005) The convention on biological diversity's 2010 target.Science 307: 212-213 The convention on biological diversity's 2010 target
52. Cheney, KL; Côté, IM. (2005) Mutualism or parasitism? The variable outcome of cleaning symbioses.Biology Letters 1: 162-165 Mutualism or parasitism? The variable outcome of cleaning symbioses
Caribbean; ectoparasites; Elacatinus species; geographical variation; interspecific interactions
The exact nature of many interspecific interactions remains unclear, with some evidence suggesting mutualism and other evidence pointing to parasitism for the same pair of interacting species. Here, we show spatial variation in the outcome of the cleaning relationship between Caribbean cleaning gobies (Elacatinus evelynae) and longfin damselfish (Stegastes diencaeus) over the distribution range of these species, and link this variation to the availability of ectoparasites. Cleaning interactions at sites with more ectoparasites were characterized by greater reductions in ectoparasite loads on damselfish clients and lower rates of removal of scales and mucus (i.e. cheating) by cleaning gobies, whereas the opposite was observed at sites where ectoparasite abundance was lower. For damselfish clients, cleaning was therefore clearly mutualistic in some locations, but sometimes neutral or even parasitic in others. Seasonal variability in ectoparasite abundance may ensure that locally low parasite availability, which promotes cleanerfish cheating, may be a transient condition at any given site. Conflicting conclusions about the nature of cleaning symbioses may, therefore, be explained by variation in ectoparasite abundance.
50. Côté, IM; Gill, JA; Gardner, TA; Watkinson, AR. (2005) Measuring coral reef decline through meta-analyses.Philosophical Transactions of the Royal Society B-Biological Sciences 360: 385-395 Measuring coral reef decline through meta-analyses
meta-analysis; large-scale; coral-algal phase shifts; Caribbean; habitat loss; habitat degradation
Coral reef ecosystems are in decline worldwide, owing to a variety of anthropogenic and natural causes. One of the most obvious signals of reef degradation is a reduction in live coral cover. Past and current rates of loss of coral are known for many individual reefs; however, until recently, no large-scale estimate was available. In this paper, we show how meta-analysis can be used to integrate existing small-scale estimates of change in coral and macroalgal cover, derived from in situ surveys of reefs, to generate a robust assessment of long-term patterns of large-scale ecological change. Using a large dataset from Caribbean reefs, we examine the possible biases inherent in meta-analytical studies and the sensitivity of the method to patchiness in data availability. Despite the fact that our meta-analysis included studies that used a variety of sampling methods, the regional estimate of change in coral cover we obtained is similar to that generated by a standardized survey programme that was implemented in 1991 in the Caribbean. We argue that for habitat types that are regularly and reasonably well surveyed in the course of ecological or conservation research, meta-analysis offers a cost-effective and rapid method for generating robust estimates of past and current states.
49. Fish, MR; Côté, IM; Gill, JA; Jones, AP; Renshoff, S; Watkinson, AR. (2005) Predicting the impact of sea-level rise on Caribbean sea turtle nesting habitat.Conservation Biology 19: 482-491 Predicting the impact of sea-level rise on Caribbean sea turtle nesting habitat
climate change; geographic information system (GIS); habitat loss; turtle nesting beaches
The projected rise in sea level is likely to increase the vulnerability of coastal zones in the Caribbean, which are already under pressure from a combination of anthropogenic activities and natural processes. One of the major effects will be a loss of beach habitat, which provides nesting sites for endangered sea turtles. To assess the potential impacts of sea-level rise on sea turtle nesting habitat, we used beach profile measurements of turtle nesting beaches on Bonaire, Netherlands Antilles, to develop elevation models of individual beaches in a geographic information system. These models were then used to quantify areas of beach vulnerable to three different scenarios of a rise in sea level. Physical characteristics of the beaches were also recorded and related to beach vulnerability, flooding, and nesting frequency. Beaches varied in physical characteristics and therefore in their vulnerability to flooding. Up to 32% of the total current beach area could be lost with a 0.5-m rise in sea level, with lower, narrower beaches being the most vulnerable. Vulnerability varied with land use adjacent to the beach. These predictions about loss of nesting habitat have important implications for turtle populations in the region.
48. Gardner, TA; Côté, IM; Gill, JA; Grant, A; Watkinson, AR. (2005) Hurricanes and Caribbean coral reefs: Impacts, recovery patterns, and role in long-term decline.Ecology 86: 174-184 Hurricanes and Caribbean coral reefs: Impacts, recovery patterns, and role in long-term decline
Caribbean coral reefs; conservation; coral decline; disturbance; hurricanes; large-scale patterns; temporal trends
The decline of corals on tropical reefs is usually ascribed to a combination of natural and anthropogenic factors, but the relative importance of these causes remains unclear. In this paper, we attempt to quantify the contribution of hurricanes to Caribbean coral cover decline over the past two decades using meta-analyses. Our study included published and unpublished data from 286 coral reef sites monitored for variable lengths of time between 1980 and 2001. Of these, 177 sites had experienced hurricane impacts during their period of survey. Across the Caribbean, coral cover is reduced by similar to17%, on average, in the year following a hurricane impact. The magnitude of this immediate loss increases with hurricane intensity and with the time elapsed since the last impact. In the following year, no further loss is discernible, but the decline in cover then resumes on impacted sites at a rate similar to the regional background rate of decline for nonimpacted sites. There is no evidence of recovery to a pre-storm state for at least eight years after impact. Overall, coral cover at sites impacted by a hurricane has declined at a significantly faster rate (6% per annum) than nonimpacted sites (2% per annum), due almost exclusively to higher rates of loss in the year after impact in the 1980s. While hurricanes, through their immediate impacts, appear to have contributed to changing coral cover on many Caribbean reefs in the 1980s, the similar decline in coral cover at impacted and nonimpacted sites in the 1990s suggests that other stressors are now relatively more important in driving the overall pattern of change in coral cover in this region. The overall lack of post-hurricane recovery points to a general impairment of the regeneration potential of Caribbean coral reefs.
47. Hernandez-Velazquez, FD; Galindo-Sanchez, CE; Taylor, MI; de la Rosa-Velez, J; Côté, IM; Schramm, Y; Aurioles-Gamboa, D; Rico, C. (2005) New polymorphic microsatellite markers for California sea lions (Zalophus californianus).Molecular Ecology Notes 5: 140-142 New polymorphic microsatellite markers for California sea lions (Zalophus californianus)
microsatellites; otariidae; pinniped; Zalophus californianus californianus
Nine microsatellite loci were isolated and characterized from California sea lions Valophus californianus). In addition, two of five loci tested from harbour seal Phoca vitulina) produced a single, clear band in Z. californianus, as did one out of five loci from grey seal (Halichoerus grypus) and one out of two loci from elephant seal (Mirounga sp.). No locus tested from South American fur seal (Arctocephalus australis) amplified in Z. californianus. Locus variability was assessed in California sea lions from Los Islotes rookery, Baja California Sur, Mexico. All loci were variable, with allele numbers ranging from three to 12.
46. McWilliams, JP; Côté, IM; Gill, JA; Sutherland, WJ; Watkinson, AR. (2005) Accelerating impacts of temperature-induced coral bleaching in the Caribbean.Ecology 86: 2055-2060 Accelerating impacts of temperature-induced coral bleaching in the Caribbean
Caribbean; climate change; coral bleaching; sea surface temperature; thermal stress
Coral bleaching is a stress-related response that can be triggered by elevated sea surface temperatures (SST). Recent increases in the frequency of coral bleaching have led to concerns that increases in marine temperatures may threaten entire coral reef regions. We report exponential increases in the geographical extent and intensity of coral bleaching in the Caribbean with increasing SST anomalies. A rise in regional SST of 0.1 degrees C results in 35% and 42% increases in the geographic extent and intensity of coral bleaching, respectively. Maximum bleaching extent and intensity are predicted to occur at regional SST anomalies of less than + 1 degrees C, which coincides with the most conservative projections for warming in the Caribbean by the end of the 21st century. Coral bleaching is therefore likely to become a chronic source of stress for Caribbean reefs in the near future.
45. Uyarra, MC; Côté, IM; Gill, JA; Tinch, RRT; Viner, D; Watkinson, AR. (2005) Island-specific preferences of tourists for environmental features: Implications of climate change for tourism-dependent states.Environmental Conservation 32: 11-19 Island-specific preferences of tourists for environmental features: Implications of climate change for tourism-dependent states
Caribbean; climate change; coral bleaching; environment management; sea level rise; tourism
Climate change may affect important environmental components of holiday destinations, which might have repercussions for tourism-dependent economics. This study documents the importance of environmental attributes in determining the choice and holiday enjoyment. of tourists visiting Bonaire and Barbados, two Caribbean islands with markedly different tourism markets and infrastructure. Three hundred and sixteen and 338 participants from Bonaire and Barbados, respectively, completed standardized questionnaires. Warm temperatures, clear waters and low health risks were the most important environmental features determining holiday destination choice. However, tourists in Bonaire thereafter prioritized marine wildlife attributes (i.e. coral and fish diversity and abundance) over other environmental features, whereas tourists in Barbados exhibited stronger preferences for terrestrial features, particularly beach characteristics. The willingness of tourists to revisit these islands was strongly linked to the state of the preferred environmental attributes. More than 80% of tourists in Bonaire and Barbados would be unwilling to return for the same holiday price in the event, respectively, of coral bleaching as a result of elevated sea surface temperatures and reduced beach area as a result of sea level rise. Climate change might have a significant impact on Caribbean tourism economy through alteration of environmental features important to destination selection. Island-specific management strategies,, such as focusing resources on the protection of key marine or terrestrial features, may provide a means of reducing the environmental and economic impacts of climate change.
44. Côté, IM; Cheney, KL. (2004) Distance-dependent costs and benefits of aggressive mimicry in a cleaning symbiosis.Proceedings of the Royal Society of London Series B-Biological Sciences 271: 2627-2630 Distance-dependent costs and benefits of aggressive mimicry in a cleaning symbiosis
aggressive mimicry; Batesian mimicry; coral reef fish; Labroides dimidiatus; Plagiotremus rhinorhynchos; Plagiotremus tapeinosoma
In aggressive mimicry, a 'predatory' species resembles a model that is harmless or beneficial to a third species, the 'dupe'. We tested critical predictions of Batesian mimicry models, i.e. that benefits of mimicry to mimics and costs of mimicry to models should be experienced only when model and mimic co-occur, in an aggressive mimicry system involving juvenile bluestreaked cleaner wrasse (Labroides dimidiatus) as models and bluestriped fangblennies (Plagiotremus rhinorhynchos) as mimics. Cleanerfish mimics encountered nearly twice as many potential victims and had higher striking rates when in proximity to than when away from the model. Conversely, in the presence of mimics, juvenile cleaner wrasses were visited by fewer clients and spent significantly less time foraging. The benefits to mimic and costs to model thus depend on a close spatial association between model and mimic. Batesian mimicry theory may therefore provide a useful initial framework to understand aggressive mimicry.
43. Neff, BD; Cargnelli, LM; Côté, IM. (2004) Solitary nesting as an alternative breeding tactic in colonial nesting bluegill sunfish (Lepomis macrochirus).Behavioral Ecology and Sociobiology 56: 381-387 Solitary nesting as an alternative breeding tactic in colonial nesting bluegill sunfish (Lepomis macrochirus)
coloniality; mating systems; tactic; female choice; bluegill
Colonial breeding can evolve in response to benefits afforded by clumped individuals, such as reduced predation and increased ease of assessing potential mates. However, colonial breeding can also impose costs such as increased disease transmission or increased cuckoldry. Here, we investigate solitary nesting as a potential alternative breeding tactic in colonial breeding bluegill sunfish (Lepomis macrochirus). Most male bluegill, termed parentals, compete for nesting sites in colonies and then court and spawn with females and provide sole care of the eggs. Although nesting in a colony results in reduced predation and fungal infection of broods, it comes at a cost of increased parasitism by specialized cuckolder males that do not nest. We found that 4.5% of parentals forgo spawning in a colony and instead construct nests solitarily. Solitary males were of similar size and age to colonial males, but were in significantly better condition. Solitary males obtained as many eggs as males nesting in the center of colonies, and significantly more than males nesting on the periphery of colonies. Thus, females do not appear to discriminate against solitary males. Solitary males had smaller ear tabs, a presumed sexually selected character used by parental males in intrasexual competition, than colonial males. Tracking data revealed consistency in nesting tactic (but not nest position within the colony) between spawning attempts. We suggest that solitary nesting represents either a facultative decision made by parental males in top condition at the onset of breeding, or a life history decision to forgo spawning in colonies.
42. Sikkel, PC; Cheney, KL; Côté, IM. (2004) In situ evidence for ectoparasites as a proximate cause of cleaning interactions in reef fish.Animal Behaviour 68: 241-247 In situ evidence for ectoparasites as a proximate cause of cleaning interactions in reef fish
Although cleaning interactions are deemed a textbook example of mutualism, there is limited evidence that clients benefit from cleaning in terms of reduced ectoparasite loads. The proximate causes of cleaning behaviour are also contentious. We examined the effect of ectoparasite load (i.e. the number of larval gnathiid isopods) on client behaviour under natural conditions. Diel variation in gnathiid loads of longfin damselfish, Stegastes diencaeus, a common coral reef fish client of cleaning gobies (Elacatinus spp.), was correlated with variation in gnathiid emergence from the substratum at sites in both Puerto Rico and St John, northeastern Caribbean. Both benthic emergence of gnathiids and their infestation on damselfish peaked in the morning. Concomitantly, clients spent significantly more time posing for and being inspected by cleaners in the morning than at other times of day. Our results corroborate recent experimental results on captive clients and are consistent with the mutualistic interpretation of cleaning symbioses. (C) 2004 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
41. Stummer, LE; Weller, JA; Johnson, ML; Côté, IM. (2004) Size and stripes: how fish clients recognize cleaners.Animal Behaviour 68: 145-150 Size and stripes: how fish clients recognize cleaners
Little is known of how individuals find each other in interspecific mutualisms involving free-living partners. We tested the importance of two factors, namely body size and the presence of a lateral body stripe, in the recognition of cleanerfish by their fish clients. Clients on an Indonesian reef flat readily approached wooden models of the bluestreak cleaner wrasse, Labroides dimidiatus, which varied in size and stripe characteristics.. The composition of the clientele of models was not significantly different from that of natural cleaning stations, suggesting that fish visiting the models were seeking to be cleaned. Normal-sized models of cleaner wrasses attracted significantly more clients, which showed more intense interest and stayed with the models for. significantly longer, than super-sized models. For normal-sized models, the number of clients increased as the length of the cleaner's lateral stripe increased (from 0, to 44, 67 and 100% of body length). However, there was no effect of stripe length on client numbers for super-sized models. Client interest also did not vary with stripe length for models of either size. Small body size and the presence of a lateral stripe therefore appear to be long-distance signals that their bearer may be a cleaner, but after initial attraction, client interest is maintained by other cues. Alternative short-distance signals,may include colour, other visual signals such as cleanerfish dances, or physical contact between cleaner and client. (C) 2004 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
40. Whiteman, EA; Côté, IM. (2004) Individual differences in microhabitat use in a Caribbean cleaning goby: a buffer effect in a marine species?Journal of Animal Ecology 73: 831-840 Individual differences in microhabitat use in a Caribbean cleaning goby: a buffer effect in a marine species?
coral reefs; density dependence; Elacatinus spp.; habitat selection; intraspecific competition
1. Buffer effects occur when changes in population size result in the disproportionate use of poor-quality habitats. Thus, at low population sizes high-quality habitats are used preferentially. As population size increases an increasing proportion of the population uses poorer-quality habitats. Assessment of the temporal and spatial variation in patterns of habitat occupancy can therefore shed light on the differences in quality between habitats and the individual fitness consequences of habitat choice. 2. We provide the first evidence of the potential operation of a buffer effect for a site-attached marine species. Caribbean cleaning gobies Elacatinus prochilos (Bohlke & Robins) occupy coral and sponge on fringing reefs in Barbados. For adult gobies, resource selection indices suggested a preference for sponge. However, as cleaning goby population size increased, the number of adult cleaning gobies occupying sponge increased more rapidly than the number occupying coral. In contrast, adults preferentially re-colonized coral following experimental removals and at these low population densities the rate of population increase was greater on coral. Our results suggest that coral may be the preferred habitat, but in Barbados this habitat becomes saturated at very low population densities as a consequence of low client densities and ectoparasite loads. Thus, a larger proportion of the population occupies sponge at most observed population densities. 3. Patterns of habitat occupancy with population size for recruits and juveniles suggest only a small difference in habitat quality between sponge and coral. Indeed, recruits and juveniles do not discriminate between sponge and coral. The population shift towards sponge rather than coral occupancy between recruitment and maturity may arise as a combination of differing survival of recruits and juveniles on coral and sponge and active movement of individuals towards sponge. 4. Our results demonstrate that interactions among individuals are an integral part of population distribution and dynamics and are therefore important in future studies of habitat choice and its associated fitness consequences.
39. Whiteman, EA; Côté, IM. (2004) Monogamy in marine fishes.Biological Reviews 79: 351-375 Monogamy in marine fishes
mate guarding; net benefit; territorial defence; mating systems; paternal care
The formation of long-term pair bonds in marine fish has elicited much empirical study. However, the evolutionary mechanisms involved remain contested and previous theoretical frameworks developed to explain monogamy in birds and mammals are not applicable to many cases of monogamy in marine fish. In this review, we summarise all reported occurrences of social monogamy in marine fish, which has so far been observed in 18 fish families. We test quantitatively the role of ecological and behavioural traits previously suggested to be important for the evolution of monogamy and show that monogamous species occur primarily in the tropics and are associated with coral reef environments in which territory defence and site attachment is facilitated. However, there is little evidence that obligately monogamous species are smaller in body size than species that can adopt. system. We review the evidence pertaining to six hypotheses suggested for the evolution a polygynous mating system. We review the evidence pertaining to six hypotheses suggested for the evolution of monogamous pair bonds: (1) biparental care, (2) habitat limitation, (3) low population density/low mate availabilivy/low mobility, (4) increased reproductive efficiency, (5) territory defence, and (6) net benefit of single mate sequestration. We outline predictions and associated empirical tests that can distinguish between these hypotheses, and assess how generally each hypothesis explains monogamy within and between breeding periods for species with different types of territories (i.e. feeding only or feeding and breeding). Hypotheses (1) and (2) have limited applicability to marine fishes, while hypotheses (3)-(5) have little empirical support beyond the species for which they were designed. However, the role of paternal care in promoting monogamous pair bonds is not explicit in these hypotheses, yet paternal care has been reported in more than 70 monogamous marine fish. We show that paternal care may act to increase the likelihood of monogamy in combination with each of the proposed hypotheses through decreased benefits to males from searching for additional mates or increased advantages to females from sequestering a single high-quality mate. Among species defending breeding and feeding territories, the benefits, both within and between reproductive periods, of sequestering a single high-quality mate (hypothesis 6) appear to be the best explanation for socially monogamous pairs. For species without parental care (i.e. holding only feeding territories), territory defence (hypothesis 5) in combination with the benefits of guarding a large mate (hypothesis 6) could potentially explain most instances of monogamy. Empirical studies of marine fishes over the past two decades are therefore slowly changing the view of monogamy from a mating system imposed upon species by environmental constraints to one with direct benefits to both sexes.
38. Whiteman, EA; Côté, IM. (2004) Dominance hierarchies in group-living cleaning gobies: causes and foraging consequences.Animal Behaviour 67: 239-247 Dominance hierarchies in group-living cleaning gobies: causes and foraging consequences
In species living in social groups, aggression among individuals to gain access to limiting resources can lead to the formation of stable social hierarchies. We tested whether dominance rank in social groups of sponge-dwelling cleaning gobies Elacatinus prochilos in Barbados was determined by physical attributes of individuals or by prior experience of dominance, and examined the foraging consequences of dominance rank. Intraspecific aggression within groups resulted in stable dominance hierarchies that were strongly correlated with fish length. Dominant individuals maintained exclusive territories while subordinate fish occupied broader home ranges. Larger, competitively dominant fish were able to monopolize areas inside the sponge lumen with the highest abundance of the polychaete Haplosyllis spp., a favoured prey item, and achieved the highest foraging rates. The removal of a territorial individual from large groups resulted in a domino-like effect in territory relocation of the remaining fish as individuals moved to the territory previously occupied by the individual just above them in the group hierarchy. Individuals added to existing groups generally failed to gain access to territories, despite being formerly dominant in their original groups. When given the opportunity to choose a location in the absence of larger competitors, gobies frequently preferred positions that were previously defended and that had abundant food. These results suggest that intraspecific competition for resources creates the observed dominance structures and provides support for the role of individual physical attributes in the formation and maintenance of dominance hierarchies. (C) 2004 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
36. Cheney, KL; Côté, IM. (2003) Do ectoparasites determine cleaner fish abundance? Evidence on two spatial scales.Marine Ecology-Progress Series 263: 189-196 Do ectoparasites determine cleaner fish abundance? Evidence on two spatial scales
cleaning symbiosis; reef fish community structure; Gobiosoma spp.
Cleaner fish on coral reefs can have a significant impact on the diversity and distribution of their fish clients. Understanding the factors affecting the distribution of cleaners themselves therefore becomes an important consideration for elucidating the mechanisms controlling coral reef fish community structure. We hypothesised that obligate cleaner fish, which rely almost exclusively on ectoparasites gleaned from clients, should be more abundant in areas rich in their preferred prey, namely parasitic gnathiid isopod larvae. We tested predictions from this hypothesis on 2 spatial scales in the Caribbean: among reefs within Barbados, and among 6 islands spanning the Greater and Lesser Antilles. As predicted, densities of coral-dwelling cleaning gobies Elacatinus spp., which are active cleaners, were higher in areas of high rates of emergence of gnathiid larvae from the benthos. This relationship was not observed in sponge-dwelling cleaning gobies, which rely mainly on non-client-gleaned food sources. The density of coral-dwelling cleaners was also correlated with client density, but contrary to our prediction was not related to ectoparasite loads of a common reef fish client. Cleaning goby abundance is more likely to be a consequence than a cause of ectoparasite availability, since cleaning goby recruitment is usually linked to factors related to foraging, and territorial clients do not preferentially settle near cleaning gobies. Whether the link between cleaner abundance and ectoparasite availability is mediated through differential recruitment or differential survival of cleaners in parasite-rich and parasite-poor areas remains to be determined.
35. Cheney, KL; Côté, IM. (2003) The ultimate effect of being cleaned: does ectoparasite removal have reproductive consequences for damselfish clients?Behavioral Ecology 14: 892-896 The ultimate effect of being cleaned: does ectoparasite removal have reproductive consequences for damselfish clients?
cleaning behavior; Elacatinus spp; Gnathiidae; Gobiosoma spp; reproductive success; Stegastes diencaeus
The mutualistic nature of cleaning symbioses has long remained unconfirmed because of the difficulty in showing net benefits for clients. We have previously shown that cleaning gobies (Elacatinus spp.) within territories of Caribbean longfin damselfish (Stegastes diencaeus) reduce the number of gnathiid isopod ectoparasites on territory owners. We now investigate whether this benefit of being cleaned has reproductive consequences for male longfin damselfish. The mating success, rate of egg loss, and parental aggression of 40 nest-guarding males were assessed during six consecutive monthly reproductive periods. Ten males had cleaning stations within their territory, 10 males were without cleaning stations, and 20 males initially with a cleaning station had their cleaners removed half-way through the study. Ectoparasite loads on our focal fish were very low; however, damselfish with cleaning stations still had significantly fewer ectoparasites than did fish without cleaning stations. There was, however, no significant difference in the number of eggs, clutches, or area of clutches received, or in the number of eggs lost before hatching between damselfish with and without cleaners. We also found no difference in parental male aggression between damselfish with and without cleaners. We conclude that although ectoparasite removal appears to have no direct consequence for reproduction, at least for the levels of infestations observed on our study site, it may still affect other aspects of damselfish fitness such as survival.
34. Cheney, KL; Côté, IM. (2003) Indirect consequences of parental care: sex differences in ectoparasite burden and cleaner-seeking activity in longfin damselfish.Marine Ecology-Progress Series 262: 267-275 Indirect consequences of parental care: sex differences in ectoparasite burden and cleaner-seeking activity in longfin damselfish
cleaning stations; paternal care; reef fish distribution; stegastes diencaeus; sex differences; territoriality
Many direct costs of parental care have been described for teleost fishes, including reduced body weight, body fat and immune condition. However, few studies have focussed on the indirect consequences of reproduction. In this study, we investigated such consequences in the longfin damselfish Stegastes diencaeus (Jordan & Rutter), a territorial reef fish in which the males provide parental care of eggs. More specifically, we examined patterns of spatial distribution of males and females in relation to substratum suitability for the establishment of nest sites and the consequences of spatial distribution for ectoparasite burden and cleaner-seeking activity. The territories of males and females differed significantly in a number of habitat features. Breeding males, with a nest site present in their territory, were found mainly at the periphery of reef patches, near sand, where vertical substratum suitable for nest sites is present, whereas females and non-breeding males were found in the centre of patches. Cleaning stations occupied by the cleaning gobies Elacatinus evelynae and E. prochilos were also located in peripheral areas, thus, in general, breeding males were closer to cleaning stations than females. Damselfish that were closer to cleaning stations visited them more frequently. During nest-guarding periods, males visited cleaning stations less frequently than during non-guarding periods, but this was not concomitant with an increase in ectoparasite loads during nest-guarding periods. Damselfish in peripheral territories had significantly lower ectoparasite numbers than those situated in the centre of reef patches. These results are consistent with a lower exposure of peripheral damselfish to ectoparasites. These intersexual differences in territory position, proximity to and use of cleaning stations, and ectoparasite loads are indirect consequences of sex differences in reproductive-resource requirements. Such interactions between breeding systems, distributional ecology and other aspects of non-reproductive behaviour are undoubtedly widespread, and their consideration could enhance our general understanding of reef-fish ecology.
33. Cheney, KL; Côté, IM. (2003) Habitat choice in adult longfin damselfish: territory characteristics and relocation times.Journal of Experimental Marine Biology and Ecology 287: 1-12 Habitat choice in adult longfin damselfish: territory characteristics and relocation times
Eupomacentrus diencaeus; habitat selection; reef fish distribution; territoriality
Habitat selection by coral reef fish during initial settlement has been shown to depend on various biotic and abiotic characteristics. However, relatively little is known of the factors influencing habitat choice by adults during post-settlement processes such as relocation or migration. In this study, we first characterised the habitat of longfin damselfish (Stegastes diencaeus Jordan and Rutter) territories to quantify territory variability. Characteristics such as percentage cover of rock, sand, live coral and distance from sand were highly variable, while territory area, turf and macro algae cover were relatively uniform across territories. We then assessed the importance of specific habitat characteristics by experimentally removing damselfish and measuring recolonisation times in relation to these characteristics, The presence of nest sites markedly increased the speed of territory recolonisation after experimental removals. Other variable territory characteristics such as substrate type, rugosity and the presence of cleaning stations did not affect recolonisation speed, In general, males recolonised territories faster than females, and males were more likely to recolonise territories previously owned by males with an active nest site. Thus, intraspecific competition for high-quality nest sites may generate sex differences in territory relocation and highly stable sex-specific patterns of adult distribution. (C) 2002 Elsevier Science B.V. All rights reserved.
32. Côté, IM; Molloy, PP. (2003) Temporal variation in cleanerfish and client behaviour: Does it reflect ectoparasite availability?Ethology 109: 487-499 Temporal variation in cleanerfish and client behaviour: Does it reflect ectoparasite availability?
We tested the importance of ectoparasites as the proximate cause of cleaning interactions by comparing the activity of Caribbean cleaning gobies (Elacatinus evelynae ) and of their clients during three daily periods (early morning, midday, and late afternoon) in which ectoparasite availability varied naturally. Emergence from the benthos of gnathiid isopod larvae, the main target of cleaning goby predation, was higher at night, when cleaners were inactive, than during the day. As a result, overall ectoparasite loads on client fish tended to be higher in the morning. Inspection bouts by cleaning gobies were longest in the morning, but also at midday when ectoparasite availability on clients was lower. Client fish were observed at cleaning stations most often in the afternoon, when they harboured few ectoparasites, but they were more likely to adopt incitation poses, which increase the likelihood of being cleaned, in the morning than later in the day. Most cleaner and client behaviours therefore did not change predictably in response to natural diurnal variation in ectoparasite availability. Our study suggests that the ultimate and proximate causes of cleaning behaviour need not necessarily coincide.
31. Culling, MA; Valero, IL; Côté, IM. (2003) Substratum preferences and diel activity patterns of spined loach Cobitis taenia in England: implications for conservation management.Folia Biologica-Krakow 51: 129-133 Substratum preferences and diel activity patterns of spined loach Cobitis taenia in England: implications for conservation management
Cobitis faenia; conservation; local adaptation; habitat requirements
The substratum preferences of spined loach from eastern England differed significantly between fish of different age groups, sexes, habitat origin (river or drainage ditches) and even between ditches, under experimental conditions. Spined loach from drainage ditches preferred organic sediments, while those from a river showed more variable substratum choice. Significant inter-individual differences were found in river fish, with juveniles preferring sand, while males preferred organic sediment and females gravel. In addition, these preferences often changed at night. A clear pattern of nocturnal behaviour was established. These results have implications for conservation management since the identification of habitat requirements is often based on diurnal distributions.
30. Einum, S; Fleming, IA; Côté, IM; Reynolds, JD. (2003) Population stability in salmon species: effects of population size and female reproductive allocation.Journal of Animal Ecology 72: 811-821 Population stability in salmon species: effects of population size and female reproductive allocation
density fluctuations; egg size; fecundity; phylogenetic comparisons; population dynamics
1. Population stability (i.e. level of temporal variation in population abundance) is linked commonly to levels of environmental disturbances. However, populations may also differ in their propensity to dampen or amplify the effects of exogenous forces. Here time-series of population estimates were used to test for such differences among 104 populations of six salmon species. 2. At the species level, Atlantic (Salmo salar L.), chinook (Oncorhynchus tshawytscha Walbaum) and coho salmon (O. kisutch W) were less variable than sockeye (O. nerka W) and pink salmon (O. gorbuscha W). Chum salmon (O. keta W) was more similar to sockeye and pink salmon. These differences may be related in part to differences in body size, and hence susceptibility to adverse environmental conditions, at the time when they migrate to the sea or lakes. 3. At the population level no effect of fecundity on variability was found, in contrast to findings for marine fishes, nor of egg size. Whereas substantial differences in the temporal stability of environmental factors among geographically close populations may override any effects of fecundity or egg size in fresh water, this is less likely in the marine environment where spatial autocorrelations of environmental variability are more pronounced. 4. Variation in population sizes was related positively to the duration of time-series when using standard deviations of In-transformed population estimates, and also when using linearly detrended population variation, suggesting non-linear long-term abundance trends in salmon populations that extend beyond the 7-year period of the shortest time-series. 5. When controlling for differences among species, stability increased with increasing population size, and it is hypothesized that this is due to large populations having a more complex spatial and genetic structure than small populations due to wider spatial distribution. The effects of population size on stability, as well as differences in stability among species, suggest that population- and organism-specific characteristics may interact with exogenous forces to shape salmon population dynamics.
29. Freckleton, RP; Côté, IM. (2003) Honesty and cheating in cleaning symbioses: evolutionarily stable strategies defined by variable pay-offs.Proceedings of the Royal Society of London Series B-Biological Sciences 270: 299-305 Honesty and cheating in cleaning symbioses: evolutionarily stable strategies defined by variable pay-offs
population model; game theory; positive interactions; coral reef
Game-theory models have indicated that the evolution of mixed strategies of cheating and honesty in many mutualisms is unlikely. Moreover, the mutualistic nature of interspecific interactions has often been difficult to demonstrate empirically. We present a game-theory analysis that addresses these issues using cleaning symbioses among fishes as a model system. We show that the assumption of constant pay-offs in existing models prevents the evolution of evolutionarily stable mixed strategies of cheating and honesty. However, when interaction pay-offs are assumed to be density dependent, mixed strategies of cheating and honesty become possible. In nature, cheating by clients often takes the form of retaliation by clients against cheating cleaners, and we show that mixed strategies of cheating and honesty evolve within the cleaner population when clients retaliate. The dynamics of strategies include both negative and positive effects of interactions, as well as density-dependent interactions. Consequently, the effects of perturbations to the model are nonlinear. In particular, we show that under certain conditions the removal of cleaners may have little impact on client populations. This indicates that the underlying mutualistic nature of some interspecific interactions may be difficult to demonstrate using simple manipulation experiments.
27. Gardner, TA; Côté, IM; Gill, JA; Grant, A; Watkinson, AR. (2003) Long-term region-wide declines in Caribbean corals.Science 301: 958-960 Long-term region-wide declines in Caribbean corals
We report a massive region-wide decline of corals across the entire Caribbean basin, with the average hard coral cover on reefs being reduced by 80%, from about 50% to 10% cover, in three decades. Our meta-analysis shows that patterns of change in coral cover are variable across time periods but largely consistent across subregions, suggesting that local causes have operated with some degree of synchrony on a region-wide scale. Although the rate of coral loss has slowed in the past decade compared to the 1980s, significant declines are persisting. The ability of Caribbean coral reefs to cope with future local and global environmental change may be irretrievably compromised.
26. Mills, SC; Côté, IM. (2003) Sex-related differences in growth and morphology of blue mussels.Journal of the Marine Biological Association of the United Kingdom 83: 1053-1057 Sex-related differences in growth and morphology of blue mussels
The morphology and growth pattern of male and female blue mussels (Mytilus edulis) from the north Norfolk coast, UK, were studied. In allometric terms, the external shell parameters of females grew faster relative to shell length than those of males. In absolute terms, females also grew more quickly than males for all external shell parameters and for most internal body parts. At a given age, females are therefore larger than males. Females had a higher shell to tissue weight ratio and a relatively heavier foot than males. A discriminant function incorporating age, weight and shell length, width, and height correctly sexed 81% of individuals in the sample from which it was derived. Both natural and sexual selection may be involved in the evolution of sexual dimorphism in blue mussels.
25. Whiteman, EA; Côté, IM. (2003) Social monogamy in the cleaning goby Elacatinus evelynae: ecological constraints or net benefit?Animal Behaviour 66: 281-291 Social monogamy in the cleaning goby Elacatinus evelynae: ecological constraints or net benefit?
We tested predictions from four hypotheses to explain the occurrence of long-term socially monogamous pairs in the Caribbean cleaning goby Elacatinus (=Gobiosoma) evelynae, namely (1) resource limitation, (2) low population and/or low mate density, (3) territorial defence and (4) net benefit of single-mate sequestration. We found no evidence that resources, in terms of available cleaning stations or clients to clean, were limited (1) or that after experimental goby removals, single individuals could not maintain cleaning stations alone (2). Population density was low but this did not prevent artificially widowed fish from remating quickly with individuals as large as their initial partners (3). Social monogamy in E. evelynae appears to result from the benefits associated with sequestering a large, high-quality mate (4). Both males and females showed intrasexual aggression towards experimental intruders consistent with mate guarding. Opportunities for polygynous matings by males, assessed by comparing the sizes, distances between and mating synchrony of neighbouring pairs, appeared both low and of limited value. Males therefore benefit most from guarding a larger, more fecund female. Females spent longer cleaning when paired with a large male, indicating that the benefits of guarding a high-quality mate may extend outside of the reproductive period for socially monogamous species. These results add to an increasing number of studies on coral reef fish showing mate-guarding behaviour and benefits to males and females from sequestering a single mate. (C) 2003 Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour.
23. Impey, AJ; Côté, IM; Jones, CG. (2002) Population recovery of the threatened endemic Rodrigues fody (Foudia flavicans) (Aves, Ploceidae) following reforestation.Biological Conservation 107: 299-305 Population recovery of the threatened endemic Rodrigues fody (Foudia flavicans) (Aves, Ploceidae) following reforestation
Ploceidae; weaver; Mascarene; conservation; habitat requirements
In 1999, we intensively surveyed all suitable habitat on the Mascarene Island of Rodrigues and mapped 334 territories of the threatened endemic Rodrigues fody (Foudia flavicans). In addition, we recorded 58 unpaired males, 85 juveniles, and 100 greybrown-plumaged birds; for a minimum estimated population size of 911 birds. This represents a near 100-fold increase in population size since 1968, which has been achieved in the absence of translocation or taxon-specific management. Birds were generally distributed in direct proportion to the availability of various forest types, but relatively more birds were found in mature, dense forests. Fody density at 10 selected sites, where vegetation surveys were carried out, increased significantly with increasing tree height, canopy cover and tree species diversity. This suggests that habitat management aimed at enhancing Rodrigues fody populations should focus on the protection of existing wooded valleys to allow forest maturation and expansion of afforested areas. (C) 2002 Elsevier Science Ltd. All rights reserved.
22. Showler, DA; Côté, IM; Jones, CG. (2002) Population census and habitat use of Rodrigues Warbler Acrocephalus rodericanus.Bird Conservation International 12: 211-230 Population census and habitat use of Rodrigues Warbler Acrocephalus rodericanus
The Endangered Rodrigues Warbler Acrocephalus rodericanus is endemic to the Indian Ocean island of Rodrigues, one of the world's most devastated tropical islands, its native forest having been completely destroyed since human colonization three centuries ago. It is now found in thickets and woodland dominated entirely by non-native trees and shrubs. As a step to implementing conservation initiatives, a population census and habitat study was undertaken in April-June 1999.. Using a combination of tape playback of song and point counts, at least 103 Rodrigues Warblers spread through nine wooded localities were observed, and a minimum population of 150 birds estimated. The majority (78%) and highest densities (2.3/ha) were found in habitat dominated by one introduced invasive tree, the rose-apple Syzygium jambos. Warblers were also found in plantations dominated by mahogany Swietenia mahagoni, tecoma Tabebuia pallida and Norfolk Island pine Araucaria cunninghamii, but at much lower densities (0.5/ha). Warbler densities were highest in habitat with a dense structure of small branches. There was a strong positive relationship between one index of human disturbance (number of cut branches) and warbler densities. This low-intensity cutting may promote the growth of new shoots thus perpetuating the dense vegetation structure that Rodrigues Warbler favours. At two localities, one supporting an existing population of warblers and the other prone to extirpation (shown from previous surveys), vegetation structure and composition were similar between sites, hinting that in some currently unoccupied areas, habitat is probably suitable and other factors are operating to preclude colonization and establishment. Further ecological studies would be desirable, especially to investigate the effect of nest-predation by introduced mammals and other factors suppressing warbler population growth.
21. Vinyoles, D; Côté, IM; De Sostoa, A. (2002) Nest orientation patterns in Salaria fluviatilis.Journal of Fish Biology 61: 405-416 Nest orientation patterns in Salaria fluviatilis
Blenniidae; mating success; nesting behaviour
The entrances of nests established under small stones by male river blennics Salaria fluviatilis in two rivers of the Ebro Basin in eastern Spain were randomly oriented in slow-flowing sites. In fast-flowing stretches or under large stones, however, nest entrances tended to open at an angle of c. 30degrees relative to current flow direction, i.e. near a south-east direction. As current velocity increased, males positioned their nest entrance closer and closer to the direction of flow. Selective nest entrance orientation reduced significantly the speed of current reaching the nest entrance such that current velocity was similar (5-7 cm s (-1)) for all nests, regardless of stone size, prevailing current speed, or study site. Male mating success, measured as egg clutch area, however, was not related to current speed at the nest entrance but instead, it increased with nest stone size and decreased with deviations from a south-east direction. The reasons for female river blenny preference for this specific nest orientation are unknown but may be related to patterns of water flow, and hence oxygenation of the eggs, in the nest. (C) 2002 Published by Elsevier Science Ltd on behalf of The Fisheries Society of the British Isles.
20. Whiteman, EA; Côté, IM. (2002) Cleaning activity of two Caribbean cleaning gobies: intra- and interspecific comparisons.Journal of Fish Biology 60: 1443-1458 Cleaning activity of two Caribbean cleaning gobies: intra- and interspecific comparisons
cleaning gobies; cleaning symbiosis; Gobiosoma spp.; mutualism; parasitism
Sharknose cleaning gobies Elacatinus evelynae were found predominantly in male-female pairs at cleaning stations located almost exclusively on coral heads. By contrast, broadstripe cleaning gobies Elacatinus prochilos were found at cleaning stations on two distinct substrata: coral and sponge, which were linked to marked differences in social behaviour, cleaning activity and diet. Elacatinus prochilos at coral cleaning stations were more frequently solitary or found in small groups, while groups of up to 40 individuals were observed on sponge cleaning stations. Coral-dwelling E prochilos spent, on average, 25 times longer cleaning and took 16 times more bites on clients than those on sponge, which was reflected in the larger proportion of client-gleaned material in their gut (40% v. <1%). These substratum-linked differences may result from differences in availability of food items at different cleaning stations. Few differences in cleaning activity were found between E evelynae and coral-dwelling E prochilos, although the latter contained a higher proportion of client-gleaned items (40% v. 25%). Most coral-dwelling cleaning gobies had ingested fish scales, although the variation among individuals was high (0 81 fish(-1)). Intra- and interspecific variability in cleaning activity of cleaner fishes implies that cleaning services for clients may vary significantly between cleaning stations. (C) 2002 The Fisheries Society of the British Isles. Published by Elsevier Science Ltd. Al rights reserved.
19. Whiteman, EA; Côté, IM. (2002) Sex differences in cleaning behaviour and diet of a Caribbean cleaning goby.Journal of the Marine Biological Association of the United Kingdom 82: 655-664 Sex differences in cleaning behaviour and diet of a Caribbean cleaning goby
Male and female sharknose cleaning gobies Elacatinus evelynae (Gobiidae) occupying cleaning stations in monogamous pairs differed significantly in cleaning behaviour and diet. Females spent five times longer cleaning, took more bites front clients, engaged in more cleaning events on more Client species, and cleaned at a higher rate than males. These behavioural differences tended to be reflected in the diet, with more females ingesting more client-gleaned items than males. These results are consistent with greater energetic requirements for reproduction for females. Male cleaning gobies were frequently absent from cleaning stations, presumably guarding eggs, and their presence at cleaning stations gave rise to foraging conflicts and interactions with females. The cleaning rate of females was significantly lowered by the presence of males, whether cleaning or not, whereas males cleaned for longer and took more bites when females were present. When cleaning the same client, males and females showed priority of first inspection, with females cleaning longer and taking more bites in cleaning events they initiated while males gained similar advantages in client- and male-initiated interactions. Furthermore, females initiated cleaning on larger clients, which may give them a foraging priority oil a higher-quality resource since larger clients tend to have more ectoparasites. Finally, from a client's perspective, the cleaning service provided appears better in terms of length of inspection and bites taken when both males and females are at a cleaning station than when a single cleaner is present. However, the foraging differences and interactions between male and female cleaning gobies are of little consequence to clients since the cleaning service provided is simply reapportioned between males and females rather than changed by the interactions between gobies.
18. Whiteman, EA; Côté, IM; Reynolds, JD. (2002) Do cleaning stations affect the distribution of territorial reef fishes?Coral Reefs 21: 245-251 Do cleaning stations affect the distribution of territorial reef fishes?
damselfish; habitat selection; cleaning symbioses; territoriality; cleaning gobies
We investigated the role of cleaning stations in determining the distribution of territorial reef species. Cleaner fish reduce their clients' ectoparasite loads and, therefore, proximity to cleaning stations should be advantageous for territorial fish. We focused on five damselfish species which hold permanent territories and cleaning stations occupied by cleaning gobies (Elacatinus spp.) on a Caribbean reef. Contrary to our predictions of higher densities near cleaning stations, we found that bicolor damselfish were less abundant near cleaning stations than at ecologically similar points without cleaning gobies whereas no effects were seen for longfin, dusky, yellowtail, and threespot damselfish. In addition, although damselfish densities were higher in the immediate vicinity of cleaning stations than 1.5-3 in away for most species, this was also the case at points without cleaners. Because cleaning stations are usually located on prominent coral heads or sponges, the overall significant attraction of damselfish to such structures, whether occupied by cleaning gobies or not, could reflect attraction to past or potential cleaning stations. However, it is more likely that interspecific competition and/or the low benefits of being cleaned at our study site prevent aggregation around cleaners. Cleaning stations may play only a minor rote in determining the distribution of territorial reef fishes.
17. Arnal, C; Côté, IM; Morand, S. (2001) Why clean and be cleaned? The importance of client ectoparasites and mucus in a marine cleaning symbiosis.Behavioral Ecology and Sociobiology 51: 1-7 Why clean and be cleaned? The importance of client ectoparasites and mucus in a marine cleaning symbiosis
cleaning gobies; cleaning symbiosis; Elacatinus; ectoparasites; fish mucus; gnathia
The preferences exhibited by cleaner fishes for particular client species and the high variability in rates at which various clients visit cleaning stations have remained largely unexplained. In this study, we assessed the relative importance of client ectoparasite load and mucus characteristics for the behaviour of cleaning gobies, Elacatinus spp, and their fish clients on a Barbadian fringing reef. Client species with high ectoparasite loads visited cleaning stations more often than less parasitised species. This effect was independent of body size. Frequency of visits to cleaning stations was not related to client mucus characteristics. These results suggest that the main motivation for clients to interact with cleaners is ectoparasite removal. Cleaners did not preferentially clean clients with higher ectoparasite load or better mucus, nor did they spend more time inspecting such clients. The interests of cleaners and clients therefore appear to be inconsistent. This may be due to the generally low rate of ectoparasitism on Barbadian fish compared to fish of other regions. Cleaning gobies fed at a lower rate on client species with higher loads of gnathiid isopod larvae, which may be explained if cleaners switch from eating ectoparasites to other items, such as mucus, on clients with few ectoparasites. Our estimates of caloric and protein content of fish mucus suggest that it may be as valuable a food source per unit weight as ectoparasites. However, no data are available to compare the value of each item per unit feeding time. The fact that clients with few ectoparasites still visit cleaners, albeit at a low rate, suggests that the cost of mucus removal may be low, compared to the benefit of incidental parasite removal. Thus, the outcome of cleaning interactions may remain positive, even in areas characterised by naturally low parasitism on clients.
16. Blay, N; Côté, IM. (2001) Optimal conditions for breeding of captive Humboldt penguins (Spheniscus humboldti): A survey of British zoos.Zoo Biology 20: 545-555 Optimal conditions for breeding of captive Humboldt penguins (Spheniscus humboldti): A survey of British zoos
sphenicid; husbandry; captive breeding; breeding success
We surveyed 16 British zoos and bird gardens to assess the optimal conditions for breeding of captive Humboldt penguins (Spheniscus humboldti). We obtained information on population, enclosure, and husbandry characteristics and related these variables to three measures of per capita breeding success, namely, per capita egg productivity, chick productivity, and hatching success (measured as the proportion of eggs laid that hatched). All three fitness measures increased with an increasing number of breeding pairs and total population size but were not related to population density. Once the effect of number of breeding pairs was removed statistically, chick productivity was found to be highest when nesting boxes were lined with sand and gravel instead of alternative substrata such as twigs or vegetation. Hatching success increased with increasing pool size and was highest in enclosures with concrete floors. Adult mortality in zoos was generally low and appeared related to the use of chlorine in freshwater pools and to the presence of other penguin species in Humboldt penguin displays. Several enclosure and husbandry parameters were not variable enough to assess their impact on reproduction of captive Humboldt penguins. Recommendations for optimising conditions for captive breeding of Humboldt penguins include keeping as large a population as possible in a concrete enclosure with a large pool area, while providing sand and gravel as nesting material. Bird density may be important but we 2 did not detect detrimental effects on breeding for densities up to 0.25 birds M. Adult mortality can be minimised by exhibiting Humboldt penguins in single-species display and avoiding chlorination of pool water. An experimental approach is recommended to confirm the results of this correlational study. (C) 2002 Wiley-Liss, Inc.
15. Cheney, KL; Côté, IM. (2001) Are Caribbean cleaning symbioses mutualistic? Costs and benefits of visiting cleaning stations to longfin damselfish.Animal Behaviour 62: 927-933 Are Caribbean cleaning symbioses mutualistic? Costs and benefits of visiting cleaning stations to longfin damselfish
Cleaning symbioses in the marine environment have long been held to be mutualistic interactions in which cleaners glean food from the surface of their fish clients while client ectoparasite load is reduced. However, there is limited evidence to show that clients benefit from being cleaned. We investigated the nature of a cleaner-client relationship by quantifying the costs to territorial longfin damselfish, Stegastes diencaeus, of being cleaned by cleaning gobies (Elacatinus evelynae and E. prochilos) in terms of travelling time, aggression and territorial intrusions incurred while seeking cleaners, and the benefits in terms of reduction in ectoparasite load. Travelling time to seek cleaners increased with distance from a damselfish's territory, as did the number of aggressive attacks by other territorial fish sustained by the travelling damselfish. The number of intrusions by fish on to the unguarded territory also increased, although not significantly, with time spent away from the territory. As a result, damselfish visited cleaning stations less as the distance between its territory and cleaning station increased. This variation in visit rate was related to a slight but significant reduction in the number of parasitic gnathiid isopod larvae per damselfish, suggesting that cleaning gobies significantly reduce client ectoparasite load. Longfin damselfish appeared willing to pay only limited costs to be cleaned. They travelled much further and staved away longer from their territories to perform reproductive and social activities than they did to seek cleaners. Distance-dependent variability in the costs of seeking cleaners allows damselfish to scale these costs in relation to the benefits gained and ensure that their relationship with cleaners remains mutualistic. (C) 2001 The Association for the Study of Animal Behaviour.
14. Côté, IM; Mosqueira, I; Reynolds, JD. (2001) Effects of marine reserve characteristics on the protection of fish populations: a meta-analysis.Journal of Fish Biology 59: 178-189 Effects of marine reserve characteristics on the protection of fish populations: a meta-analysis
fisheries; marine conservation; marine protected area; reefs; tropics
Meta-analyses of published data for 19 marine reserves reveal that marine protected areas enhance species richness consistently, but their effect on fish abundance is more variable. Overall, there was a slight (11%) but significant increase in fish species number inside marine reserves, with all reserves sharing a common effect. There was a substantial but non-significant increase in overall fish abundance inside marine reserves compared to adjacent, non-reserve areas. When only species that are the target of fisheries were considered, fish abundance was significantly higher (by 28%) within reserve boundaries. Marine reserves vary significantly in the extent and direction of their response. This variability in relative abundance was not attributable to differences in survey methodology among studies, nor correlated with reserve characteristics such as reserve area, years since protection, latitude nor species diversity. The effectiveness of marine reserves in enhancing fish abundance may be largely related to the intensity of exploitation outside reserve boundaries and to the composition of the fish community within boundaries. It is recommended that studies of marine reserve effectiveness, should routinely report fishing intensity, effectiveness of enforcement and habitat characteristics. (C) 2001 The Fisheries Society of the British Isles.
13. Arnal, C; Côté, IM. (2000) Diet of broadstripe cleaning gobies on a Barbadian reef.Journal of Fish Biology 57: 1075-1082 Diet of broadstripe cleaning gobies on a Barbadian reef
cleaning gobies; Elacatinus spp; cleaning behaviour; coral reef; gnathiid isopod
Gnathiid isopod larvae constituted the majority of countable food items taken by broadstripe gobies, Elacatinus prochilos, on Barbadian coral reefs, which confirms their important role in cleaning interactions. However, E. prochilos does not rely exclusively on cleaning for food since a large amount of benthic material, mainly sponge and coral polyps, was observed in the stomach contents of all cleaners. Less than one-third of cleaners had ingested ectoparasites. Elacatinus prochilos appears to consume few ectoparasites compared with other Elacatinus species elsewhere in the Caribbean and with Indo-Pacific cleaner species. (C) 2000 The Fisheries Society of the British Isles.
12. Arnal, C; Côté, IM; Sasal, P; Morand, S. (2000) Cleaner-client interactions on a Caribbean reef: influence of correlates of parasitism.Behavioral Ecology and Sociobiology 47: 353-358 Cleaner-client interactions on a Caribbean reef: influence of correlates of parasitism
cleaning gobies; cleaning symbiosis; Elacatinus; fish density; social behaviour; body size
We investigated the influence of known correlates of parasitism, namely fish density, body size and social behaviour, on three highly variable aspects of the interactions between cleaning gobies (Elacatinus spp.) and their clients, on a Barbadian coral reef. We specifically considered (1) variability in client visit rate to cleaning stations, (2) cleaning goby preference for specific clients and (3) variation in the time spent cleaning by cleaners. Using phylogenetically independent contrasts, we found that client species that were abundant on the reef visited cleaning stations more often than rarer client species. This could be due to the positive relationship between ectoparasite load and client density, or alternatively may simply reflect the frequency of contact between cleaners and clients. Cleaning gobies spent more time cleaning large-bodied clients, which usually have higher ectoparasite loads, although cleaning goby preference for clients was influenced by none of the correlates of client parasitism. Overall, factors assumed to correlate with ectoparasite load had a limited influence on the variability observed in the interactions between cleaning gobies and their clients.
11. Côté, IM. (2000) Evolution and ecology of cleaning symbioses in the sea.Oceanography and Marine Biology, Vol 38 38: 311-355 Evolution and ecology of cleaning symbioses in the sea
Cleaning symbioses are among the most intriguing interspecific interactions. Understanding their evolution has been hindered by the difficulty in identifying universal costs and benefits derived by both participants in a cleaning interaction. Their ecological role, especially within reef communities where cleaning symbioses are particularly prominent, is also not well known. This paper reviews studies of cleaning interactions (a) to examine the taxonomic distribution of cleaning behaviour, (b) to assess the magnitude and generality of various costs and benefits to cleaners and their clients in order to gain insights into the evolution of these symbioses, and (e) evaluate the role of cleaning in structuring fish communities. A total of 131 species of fishes and crustaceans have so far been described as cleaners. The majority are facultative cleaners, which glean only a small part of their food by cleaning as juveniles. Cleaners are widely distributed taxonomically, suggesting that cleaning has evolved independently several times. A paired contrasts analysis supports the idea that a small body may pre-adapt species to become cleaners, but only among facultative cleaners. There is, however, no evidence of a guild coloration in facultative cleaners, although the status of obligate cleaners appears to be signalled by the presence of bright lateral body stripes. Cleaners gain food from cleaning, with obligate cleaners obtaining on average 85% of their food from client-gleaned items, Of these, ectoparasites constitute the major proportion. There are several recorded instances of predation on cleaners by potential clients which may occur mainly during non-cleaning interactions. On the whole, however, rates of predation on cleaners are extremely low. This suggests that cleaners accrue a net benefit from cleaning. For clients, the main expected benefit of being cleaned is a reduction in ectoparasite load but this has been difficult to show due to methodological problems in quantifying ectoparasite intensity. In addition, this benefit may be measurable only in areas with naturally high rates of parasitism, such as the Great Barrier Roof where a net decrease in parasites on clients cleaned was measured recently. There is no direct evidence that the costs potentially incurred by clients when visiting cleaning stations are very high. Cleaning stations do not appear to play more than a very small role in determining the distribution of reef fishes. Although greater diversity and abundance of fishes are often found near cleaning stations, the removal of cleaners does not generally result in shifts in client species distribution. Over three decades of research on cleaning symbioses have yet to reveal unambiguously the nature of these interactions, Progress may have been slow, because of a reluctance to tackle directly the dynamics of ectoparasites. Recent studies using this approach have been fruitful. Cleaning symbioses may best be seen as co-evolutionary mosaics that vary temporally and geographically according to environmental circumstances.
10. Mosqueira, I; Côté, IM; Jennings, S; Reynolds, JD. (2000) Conservation benefits of marine reserves for fish populations.Animal Conservation 3: 321-332 Conservation benefits of marine reserves for fish populations
We synthesize the results of empirical studies of marine reserves to assess the potential benefits of protection for fish populations. Our meta-analyses demonstrate that the overall abundance of fishes inside reserves is, on average, 3.7 times higher than outside reserve boundaries. This enhancement is mainly a result of a significant increase in abundance of species that are the target of fisheries. Non-target species are equally abundant inside and outside reserves. Large-bodied species also respond more to protection, irrespective of their fishery status. Species within genera show great heterogeneity in their response to protection despite similarities in their life histories. Our study confirms that marine reserves benefit fish populations and highlights the need for monitoring prior to reserve establishment to provide more accurate, habitat-controlled studies of the effects of marine reserves on fish populations.
9. Perdices, A; Doadrio, I; Côté, IM; Machordom, A; Economidis, P; Reynolds, JD. (2000) Genetic divergence and origin of Mediterranean populations of the River Blenny Salaria fluviatilis (Teleostei : Blenniidae).Copeia : 723-731 Genetic divergence and origin of Mediterranean populations of the River Blenny Salaria fluviatilis (Teleostei : Blenniidae)
The current distribution of the River Blenny Salaria (= Blennius) fluviatilis, one of the two freshwater representatives of a large, cosmopolitan marine fish family, poses an interesting biogeographical problem because this species inhabits widely separate circum-Mediterranean watersheds. Potential scenarios of its dispersal were examined using allozyme analysis of several populations from the Iberian and Greek peninsulas. Based on Nei genetic distances, the most divergent populations were the populations inhabiting lakes, Lake Trichonis in Greece, and Ruidera Lakes in Spain. Their high divergence suggests their early isolation from the main ingroup populations. In contrast, low genetic distances were found among river populations regardless of geographic location. There was a correlation between genetic distance and geographic distance among Iberian river populations, suggesting that dispersal following the colonization of fresh water occurred via the sea to nearby, unconnected river basins. The ancestor of S. fluviatilis may have been a euryhaline species, allowing incursions into fresh water and subsequent dispersal via the sea. This dispersal scenario could theoretically be combined with multiple colonization episodes. The two old lake populations shared a unique allele at the Pgdh-A locus in high frequency with its closest relative S. pave, which was absent from other populations. This may indicate two initial incursions into fresh water by a wide-ranging marine ancestor that possessed this allele. Differential selection on this allele in lake habitats or convergence are less likely possibilities. Thus, the present distribution of S. fluviatilis appears to stem from a combination of "raceme" origins (i.e., more than one colonization episode) and subsequent dispersal and divergence in new watersheds.
8. Côté, IM; Jelnikar, E. (1999) Predator-induced clumping behaviour in mussels (Mytilus edulis Linnaeus).Journal of Experimental Marine Biology and Ecology 235: 201-211 Predator-induced clumping behaviour in mussels (Mytilus edulis Linnaeus)
group living; Homarus gammarus; predator-prey interactions; protective behaviour
This study examined the aggregation behaviour of blue mussels, Mytilus edulis, under threat of predation by European lobster, Homarus gammarus Linnaeus. Risk of predation was simulated using water in which a hungry lobster had been for 24 h, and mussels were initially set in experimental containers either near (0.5 body length apart) or far (1.5 body length apart) from each other. We found that mussels exposed to lobster effluent formed more clumps, more rapidly than mussels in control conditions. The initial distance separating the mussels had no effect on their aggregation tendencies. Overall, a greater proportion of mussels were aggregated in the lobster treatment at the end of the 22-h experiment. This was not simply the result of increased locomotion. Although mussels in lobster effluent did exhibit greater crawling speed in the first hour of the experiment, mussels initially set far apart also showed enhanced locomotion in both lobster and control treatments. Yet, of the mussels initially far from each other, those in lobster effluent formed clumps on average 5 h sooner than mussels in control water. This suggests that chemotaxis may be involved. Although mussels do aggregate under risk of predation in the laboratory, it is not yet known whether predation plays a significant role in the formation of natural mussel beds. (C) 1999 Elsevier Science B.V. All rights reserved.
7. Côté, IM; Vinyoles, D; Reynolds, JD; Doadrio, I; Perdices, A. (1999) Potential impacts of gravel extraction on Spanish populations of river blennies Salaria fluviatilis (Pisces, Blenniidae).Biological Conservation 87: 359-367 Potential impacts of gravel extraction on Spanish populations of river blennies Salaria fluviatilis (Pisces, Blenniidae)
Lipophrys fluviatilis; Blennius fluviatilis; environmental disturbance; conservation; Mediterranean freshwater
River blennies Salaria fluviatilis have a wide circum-Mediterranea distribution, but they are mostly confined to small, very localised populations. In the Iberian Peninsula, they are endangered due to a variety of causes, including gravel extraction. This study identified the breeding requirements of river blennies at a site where gravel extraction takes place and at three other sites in different drainage basins in Spain. Breeding males chose nest stones that were significantly larger than other stones available in the immediate vicinity. Although clutch area was significantly related to stone size in two of three populations, male size was not. Stone size appeared to be the main correlate of clutch size, and stone sizes were significantly smaller at sites where gravel had been extracted. The potential effects of stone and gravel removal on nesting density and egg productivity were simulated, and it was found that a 75% reduction in stone size, as observed in this study, could result in a 47% decrease in nesting density. Because of the relationship between clutch size and nest stone size, egg production would be reduced even further, to 25% of its initial level. Removal of stones and gravel from the river bed also causes structural alterations which may render the habitat unsuitable for breeding blennies despite the presence of apparently suitable nest stones. Our results may be applicable to the conservation of other substrate-spawning fish. (C) 1998 Elsevier Science Ltd. All rights reserved.
6. Vinyoles, D; Côté, IM; de Sostoa, A. (1999) Egg cannibalism in river blennies: the role of natural prey availability.Journal of Fish Biology 55: 1223-1232 Egg cannibalism in river blennies: the role of natural prey availability
Blennius fluviatilis; body condition; Lipophrys fluviatilis; parental care
The abundance of benthic macro-invertebrates, the main prey of river blennies Salaria fluviatilis, decreased drastically through the blenny reproductive season in the River Matarrana, south-east Spain. Despite this, females maintained their body condition, while the body condition of males increased. The latter coincided with the onset of egg guarding, which is carried out by males and which provided them with an opportunity to cannibalize eggs. Indeed, significantly more males than females were egg cannibals. The proportion of cannibalistic males increased as the season progressed, but the overall frequency remained low (7.4%). The number of eggs eaten was not related to the weight of macro-invertebrates ingested by males. In addition, the body condition of cannibalistic and non-cannibalistic males was similar and was not correlated with the number of eggs ingested. It is possible that non-cannibalistic males may have eaten and digested eggs Drier to capture. It is concluded that even in productive rivers such as the Matarrana, males may still rely on filial cannibalism to survive until the end of the parental care period. (C) 1999 The Fisheries Society of thr British Isles.
5. Arnal, C; Côté, IM. (1998) Interactions between cleaning gobies and territorial damselfish on coral reefs.Animal Behaviour 55: 1429-1442 Interactions between cleaning gobies and territorial damselfish on coral reefs
We studied the interactions between cleaning gobies, Elacatinus spp.. at cleaning stations and territorial dusky damselfish, Stegastes fuscus, on a Barbadian fringing reef to;enhance our understanding of the behavioural impact of cleaning stations on members of a coral reef community. Cleaning stations within damselfish territories were visited by significantly fewer species and fewer individuals than those outside damselfish territories. At cleaning stations within damselfish territories, the main client was the territory holder itself. Client behaviour did not differ between the two types of cleaning station; however, cleaning gobies at stations within damselfish territories spent less time cleaning clients? their cleaning bouts were shorter, and their feeding rate on clients was slower. These effects appear to be due to the repeated aggression of territorial damselfish towards fish intruding on to their territories to visit cleaning stations. The overlap between a territorial damselfish and a cleaning station therefore appears to have detrimental impacts on cleaning goby foraging. The presence of cleaning stations within damselfish territories exerted some effects on the territory owners. Although the rates of intrusions were similar on territories with and without cleaning stations, damselfish with cleaning stations tended to chase intruders more often, had a lower foraging rate, and were at higher risk of egg predation because of increased intrusions by egg predators. A potential benefit to territorial damselfish is regular access to a cleaning station; however, the magnitude of this benefit is unknown. This study reveals that damselfish, which are ubiquitous on coral reefs, can generate significant variation in levels of use of cleaning stations, which leads to new questions relating to the settlement behaviour of both cleaning gobies and damselfish. (C) 1998 :The Association for the Study of Animal Behaviour.
4. Côté, IM; Arnal, C; Reynolds, JD. (1998) Variation in posing behaviour among fish species visiting cleaning stations.Journal of Fish Biology 53: 256-266 Variation in posing behaviour among fish species visiting cleaning stations
cleaning symbiosis; Gobiosoma; coral reefs
The adaptive significance of posing behaviour by fish visiting cleaning stations on a Barbadian fringing reef was investigated. The probability of a visitor being cleaned by cleaning gobies (Elacatinus spp.) was significantly higher after posing than after failing to pose upon arrival at a cleaning station. Despite this, not all visitors posed, and there was much variation among species in tendency to pose. This interspecific variation was not related to the probability of being cleaned, either after posing or after failing to pose, nor was it related to trophic level or fish total length. The latter was true both for cross-species analyses and phylogenetically independent contrasts. A cost-benefit model is proposed to understand interspecific variation in posing behaviour, which considers both decisions by clients and by cleaners. As well as explaining the results, this may reconcile differences among anecdotal and experimental observations from previous studies. (C) 1998 The Fisheries Society of the British Isles.
3. Côté, IM; Reverdy, B; Cooke, PK. (1998) Less choosy or different preference? Impact of hypoxia on hermit crab shell assessment and selection.Animal Behaviour 56: 867-873 Less choosy or different preference? Impact of hypoxia on hermit crab shell assessment and selection
Hermit crabs that rely on gastropod shells for protection have to assess a number of shell features, each of which can bring different, and sometimes conflicting, advantages to their bearer. We examined how environmentally induced stress, in the form of hypoxia, can alter the relative benefits of different shell features and result in the selection of different shells by the hermit crab Pagurus bernhardus. Hermit crabs under hypoxic conditions spent significantly less time investigating shells before entering them. Despite this apparently superficial assessment, they chose shells that were well suited to hypoxic conditions; After 24 h, they were found in shells that were significantly lighter than those chosen by hermit crabs under normal oxygen. This shift in preference was achieved at the expense of the internal spaciousness of the shell, which may have deleterious implications for predation and reproduction. This cost was more evident for larger hermit crabs since there was no relationship between hermit crab size and shell characteristics for hermit crabs in hypoxia. Under oxygen stress, hermit crabs therefore alter their shell preference in favour of lighter, and thus smaller, shells, probably reflecting a greater concern for energy minimization than protection from predation or reproduction. (C) 1998 The Association for the Study of Animal Behaviour
1. Côté, IM; Sutherland, WJ. (1997) The effectiveness of removing predators to protect bird populations.Conservation Biology 11: 395-405 The effectiveness of removing predators to protect bird populations
The control of predators for nature conservation purposes is becoming an increasingly important issue. The growing populations of predator species in some areas and the introduction of predators in other areas have led to concerns about their impact on vulnerable bird species and to the implementation of predator control in some cases. This is set against a background of increasingly fragmented semi-natural habitats and declining populations for many species. To assess the efficiency of predator removal as a conservation measure, the results of 20 published studies of predator removal programs were meta-analyzed. Removing predators had a large, positive effect on hatching success of the target bird species, with removal areas showing higher hatching success, on average, than 75% of the control areas. Similarly, predator removal increased significantly post-breeding population sizes (i.e. autumn densities) of the target bird species. The effect of predator removal on breeding population sizes was not significant, however, with studies differing widely in their reported effects. We conclude that predator removal often fulfills the goal of game management, which is to enhance harvestable post-breeding populations, but that it is much less consistent in achieving the usual aim of conservation managers, which is to maintain and, where appropriate, increase bird breeding population sizes. This may be due to inherent characteristics of avian population regulation, but also to ineffective predator removal and inadequate subsequent monitoring of the prey populations.