69. Abbott, VA; Nadeau, JL; Higo, HA; Winston, ML. (2008) Lethal and sublethal effects of imidacloprid on osmia lignaria and clothianidin on megachile rotundata (Hymenoptera : megachilidae).Journal of Economic Entomology 101: 784-796 Lethal and sublethal effects of imidacloprid on osmia lignaria and clothianidin on megachile rotundata (Hymenoptera : megachilidae)
Osmia lignaria; Megachile rotundata; pesticides; sublethal effects; methodology
We examined lethal and sublethal effects of imidacloprid on Osmia lignaria (Cresson) and clothianidin on Megachile rotundata (F.) (Hymenoptera: Megachilidae). We also made progress toward developing reliable methodology for testing pesticides on wild bees for use in pesticide registration by using field and laboratory experiments. Bee larvae were exposed to control, low (3 or 6 ppb), intermediate (30 ppb), or high (300 ppb) doses of either imidacloprid or clothianidin in pollen. Field experiments on both bee species involved injecting the pollen provisions with the corresponding pesticide. Only O. lignaria was used for the laboratory experiments, which entailed both injecting the bee's own pollen provisions and replacing the pollen provision with a preblended pollen mixture containing imidacloprid. Larval development, emergence, weight, and mortality were monitored and analyzed. There were no lethal effects found for either imidacloprid or clothianidin on O. lignaria and M. rotundata. Minor sublethal effects were detected on larval development for O. lignaria, with greater developmental time at the intermediate (30 ppb) and high doses (300 ppb) of imidacloprid. No similar sublethal effects were found with clothianidin on M. rotundata. We were successful in creating methodology for pesticide testing on O. lignaria and M. rotundata; however, these methods can be improved upon to create a more robust test. We also identified several parameters and developmental stages for observing sublethal effects. The detection of sublethal effects demonstrates the importance of testing new pesticides on wild pollinators before registration.
68. Ratti, CM; Higo, HA; Griswold, TL; Winston, ML. (2008) Bumble bees influence berry size in commercial Vaccinium spp. cultivation in British Columbia.Canadian Entomologist 140: 348-363 Bumble bees influence berry size in commercial Vaccinium spp. cultivation in British Columbia
We studied the abundance, diversity, and dispersion patterns of managed and wild bee (Hymenoptera: Apoidea) populations in commercial highbush blueberry and cranberry (Ericaceae: Vaccinium corymbosum L., Vaccinium macrocarpon Air.) fields in the Fraser Valley of British Columbia, and assessed their potential as pollinators of these crops by determining which groups of bees had the greatest impact on percent yield and mass of berries. Bumble bees were evenly distributed within both crops. Other wild bee species were well distributed in blueberry fields but generally remained at edges of cranberry fields. Percent berry yield was not related to bee abundance for any group of bees, nor was species diversity correlated with berry mass. Blueberry mass and cranberry mass were related to abundance of bumble bees but not to that of honey bees or other wild bees. Bumble bees are recommended as potential alternative pollinators of these crops.
67. Grozinger, CM; Fan, YL; Hoover, SER; Winston, ML. (2007) Genome-wide analysis reveals differences in brain gene expression patterns associated with caste and reproductive status in honey bees (Apis mellifera).Molecular Ecology 16: 4837-4848 Genome-wide analysis reveals differences in brain gene expression patterns associated with caste and reproductive status in honey bees (Apis mellifera)
caste; eusociality; genomics; longevity; microarrays; reproduction
A key characteristic of eusocial species is reproductive division of labour. Honey bee colonies typically have a single reproductive queen and thousands of sterile workers. Adult queens differ dramatically from workers in anatomy, physiology, behaviour and lifespan. Young female workers can activate their ovaries and initiate egg laying; these 'reproductive' workers differ from sterile workers in anatomy, physiology, and behaviour. These differences, however, are on a much smaller scale than those observed between the queen and worker castes. Here, we use microarrays to monitor expression patterns of several thousand genes in the brains of same-aged virgin queens, sterile workers, and reproductive workers. We found large differences in expression between queens and both worker groups (similar to 2000 genes), and much smaller differences between sterile and reproductive workers (221 genes). The expression patterns of these 221 genes in reproductive workers are more queen-like, and may represent a core group of genes associated with reproductive physiology. Furthermore, queens and reproductive workers preferentially up-regulate genes associated with the nurse bee behavioural state, which supports the hypothesis of an evolutionary link between worker division of labour and molecular pathways related to reproduction. Finally, several functional groups of genes associated with longevity in other species are significantly up-regulated in queens. Identifying the genes that underlie the differences between queens, sterile workers, and reproductive workers will allow us to begin to characterize the molecular mechanisms underlying the evolution of social behaviour and large-scale remodelling of gene networks associated with polyphenisms. DOI
66. Morandin, LA; Winston, ML; Abbott, VA; Franklin, MT. (2007) Can pastureland increase wild bee abundance in agriculturally intense areas?Basic and Applied Ecology 8: 117-124 Can pastureland increase wild bee abundance in agriculturally intense areas?
pollination; agriculture; ecosystem services; canola; Brassica; conservation
Agricultural intensification and expansion are major present and future causes of global ecosystem disruption. Natural and semi-natural reserve areas in agroecosystems are thought to be important for preservation of essential ecosystem services such as pollination, but data about land use patterns and pollinator abundance are lacking. We assessed wild bee populations in canola fields in an agriculturally intense area where virtually all land was either tilled agricultural fields or semi-natural grazed pasturelands, with the expectation that mosaics of land use types may better support ecosystem services than homogenous crop areas. Fields were chosen in two categories, five with little or no pastureland (< 6%) and five with at least 15% pastureland within an 800 m distance of field edges. Fields in the high pasture category had more bumble bees and other wild bees than tow pasture fields and 94% of the variation in bumble bee abundance in fields was explained by variation in the amount of pastureland nearby. Lower bee abundance in fields with little pastureland around them could result in reduced pollination and seed set unless supplemented with managed pollinators such as honeybees. In areas with intense agriculture we show that mosaics of (and use types can be better for wild bee populations and potentially for crop production than Landscapes that are homogenous titled crop areas. Designing agricultural areas that integrate land use and ecosystem function is a practical approach for promoting sustainable agriculture practices. (c) 2006 Gesellschaft fur Okologie. Published by Elsevier GmbH. All rights reserved. DOI
65. Hoover, SER; Higo, HA; Winston, ML. (2006) Worker honey bee ovary development: seasonal variation and the influence of larval and adult nutrition.J Comp Physiol B 176: 55-63 (DOI: 10.1007/s00360-005-0032-0) Worker honey bee ovary development: seasonal variation and the influence of larval and adult nutrition
ovary; Apis mellifera; nutrition; honey bee; worker reproduction
We examined the effect of larval and adult nutrition on worker honey bee (Apis mellifera L.) ovary development. Workers were fed high or low-pollen diets as larvae, and high or low-protein diets as adults,. Workers red low-protein diets at both life stages had the lowest levels of ovary development, followed by those fed high-protein diets as larvae and low- quality diets as adults, and then those fed diets poor in protein as larvae but high as adults. Workers fed high-protein diets at both life stages had the highest levels of ovary development. The increases in ovary development due to improved dietary protein in the larval and adult life stages were additive. Adult diet also had an effect on body mass. The results demonstrate that both carry-over of larval reserves and nutrients acquired in the adult life stage are important to ovary development in worker honey bees. Carry-over from larval development, however, appears to be less important to adult fecundity than is adult nutrition. Seasonal trends in worker ovary development and mass were examined throughout the brood rearing season. Worker ovary development was lowest in spring, highest in mild-summer, and intermediate in fall.
64. Morandin, LA; Winston, ML. (2006) Pollinators provide economic incentive to preserve natural land in agroecosystems.Agr Ecosyst Environ 116: 289-292 Pollinators provide economic incentive to preserve natural land in agroecosystems
pollination; wild bees; canola; sustainable agriculture; natural land reserves; crop yield; ecosystem services
Natural habitats are considered inherently indispensable to the global economy by conservationists, but few natural ecosystems afford direct and quantifiable economic benefits. Quantification of natural land value can provide compelling evidence favoring preservation over development. Wild bees are important pollinators of many crop plants. and natural patches in agroecosystems enhance pollinator services and crop yield. Bee abundance was greatest in canola fields that had more uncultivated land within 750 m of field edges and seed set was greater in fields with higher bee abundance. A cost-benefit model that estimates profit in canola agroecosystems with different proportions of uncultivated land is presented. Yield and profit could be maximized with 30% of land uncultivated within 750 m of field edges. (c) 2006 Elsevier B.V. All rights reserved.
62. Gervan, NL; Winston, ML; Higo, HA; Hoover, SER. (2005) The effects of honey bee (Apis mellifera) queen mandibular pheromone on colony defensive behaviour.J Apicult Res 44: 175-179 The effects of honey bee (Apis mellifera) queen mandibular pheromone on colony defensive behaviour
Apis melfifera; defensive behaviour; queen mandibular pheromone; Bee Boost
Honey bee (Apis mellifera) queen mandibular pheromone (QMP) influences many aspects of worker behaviour and physiology. We observed that synthetic QMP seems to calm colonies and reduce stinging, suggesting a role for QMP in managing colony defensive behaviour. We assessed defensive responses of colonies that were queenright, queenless or supplemented with two forms of synthetic QMP (liquid QMP on glass slides or Bee Boost (R) synthetic lures) by counting stings on a leather patch and the number of responder bees at colony entrances. Colonies with queens showed decreased defensive behaviour when exposed to liquid QMP; colonies without queens and exposed to liquid QMP had no change in the number of stings but a decrease in the number of guard bees. Bee Boost had no effect on colony defensive behaviour in colonies with or without queens. The ability to reduce defensive behaviour with QMP could have positive implications for commercial beekeeping, especially in context with Africanized bees, should an effective release device be developed.
61. Hoover, SER; Oldroyd, BP; Wossler, TC; Winston, ML. (2005) Anarchistic queen honey bees have normal queen mandibular pheromones.Insectes Sociaux 52: 6-10 Anarchistic queen honey bees have normal queen mandibular pheromones
Apis mellifera; anarchy; QMP; laying workers; queen mandibular pheromones
Anarchistic honey bees are a line developed by recurrent selection in which workers frequently lay eggs. In unselected colonies, workers refrain from reproduction in response to pheromonal signals that indicate the presence of brood and a queen. We show that queen type (anarchistic or wild type) has no effect on rates of ovary activation of anarchistic or wild type workers. In addition, we show that an important component of the queen's signalling system, the queen mandibular gland pheromone, is similar in wild type and anarchistic queens. Anarchistic larvae do not inhibit worker ovary development to the same degree as wild type larvae, however all colonies in this experiment contained only wild type larvae. Anarchistic workers had greater rates of ovary activation than wild type workers in colonies headed by either queen type. We therefore conclude that there must be differences in the transmission or reception of queen pheromones, or worker sensitivity to these compounds. These results clearly demonstrate that anarchy is a complex syndrome, not simply the result of reduced pheromone production by anarchist queens and larvae.
60. Hoover, SER; Winston, ML; Oldroyd, BP. (2005) Retinue attraction and ovary activation: responses of wild type and anarchistic honey bees (Apis mellifera) to queen and brood pheromones.Behavioral Ecology and Sociobiology 59: 278-284 Retinue attraction and ovary activation: responses of wild type and anarchistic honey bees (Apis mellifera) to queen and brood pheromones
anarchy; Apis mellifera; ovary development; worker reproduction; pheromones; QMP; ovary activation
In most social insect colonies, workers do not attempt to lay eggs in the presence of a queen. However, in the honey bee (Apis mellifera), a rare phenotype occurs in which workers activate their ovaries and lay large numbers of male eggs despite the presence of a fecund queen. We examined the proximate mechanisms by which this 'anarchistic' behaviour is expressed. We tested the effects of brood and queen pheromones on retinue attraction and worker ovary activation using caged worker bees. We found no difference between the anarchistic and wild type queen pheromones in the retinue response elicited in either wild type or anarchistic workers. Further, we found that anarchistic queens produce a pheromone blend that is as effective at inhibiting ovary activation as the wild type queen pheromone. However, anarchistic workers are less inhibited by queen pheromones than their wild type counterparts, in a dose-dependent manner. These results show that the anarchistic phenomenon is not due to changes in the production of queen pheromones, but rather is due in part to a shift in the worker response to these queen-produced signals. In addition, we demonstrate the dose-dependent nature of the effect of queen pheromones on honey bee worker ovary activation.
59. Morandin, LA; Winston, ML. (2005) Wild bee abundance and seed production in conventional, organic, and genetically modified canola.Ecological Applications 15: 871-881 Wild bee abundance and seed production in conventional, organic, and genetically modified canola
agriculture; bees; Brassica rapa; Brassica napus; canola; conventional; genetically modified; organic; pollination; sustainable development
The ecological impacts of agriculture are of concern, especially with genetically modified and other intensive, modern cropping systems, yet little is known about effects on wild bee populations and subsequent implications for pollination. Pollination deficit (the difference between potential and actual pollination) and bee abundance were measured in organic, conventional, and herbicide-resistant, genetically modified (GM) canola fields (Brassica napus and B. rapa) in northern Alberta, Canada, in the summer of 2002. Bee abundance data were collected using pan traps and standardized sweep netting, and pollination deficit was assessed by comparing the number of seeds per fruit from open-pollinated and supplementally pollinated flowers. There was no pollination deficit in organic fields, a moderate pollination deficit in conventional fields, and the greatest pollination deficit in GM fields. Bee abundance was greatest in organic fields, followed by conventional fields, and lowest in GM fields. Overall, there was a strong, positive relationship between bee abundance at sampling locations and reduced pollination deficits. Seed set in B. napus increased with greater bee abundance. Because B. rapa is an obligate outcrossing species, the lack of pollination deficit in the organic (B. rapa) fields likely was due to the high bee abundance rather than a lower dependence of B. rapa on pollinators than B. napus canola. Our study illustrates the importance of wild bees to agricultural production and suggests that some agroecosystems may better sustain wild bee abundance, resulting in greater seed production. Further research on why some cropping systems, such as genetically modified, herbicide-resistant canola, have low wild bee abundance would be useful for management of agroecosystems to promote sustainability of food production.
58. Morandin, LA; Winston, ML; Franklin, MT; Abbott, VA. (2005) Lethal and sub-lethal effects of spinosad on bumble bees (Bombus impatiens Cresson).Pest Management Science 61: 619-626 Lethal and sub-lethal effects of spinosad on bumble bees (Bombus impatiens Cresson)
pesticides; bumblebees; toxicity; spinosad; sub-lethal effects; foraging
Recent developments of new families of pesticides and growing awareness of the importance of wild pollinators for crop pollination have stimulated interest in potential effects of novel pesticides on wild bees. Yet pesticide toxicity studies on wild bees remain rare, and few studies have included long-term monitoring of bumble bee colonies or testing of foraging ability after pesticide exposure. Larval bees feeding on exogenous pollen and exposed to pesticides during development may result in lethal or sublethal effects during the adult stage. We tested the effects of a naturally derived biopesticide, spinosad, on humble bee (Bombus impatiens Cresson) colony health, including adult mortality, brood development, weights of emerging bees and foraging efficiency of adults that underwent larval development during exposure to spinosad. We monitored colonies from an early stage, over a 10-week period, and fed spinosad to colonies in pollen at four levels: control, 0.2, 0.8 and 8.0 mg kg(-1), during weeks 2 through 5 of the experiment. At concentrations that bees would likely encounter in pollen in the wild (0.2-0.8 mg kg(-1)) we detected minimal negative effects to humble bee colonies. Brood and adult mortality was high at S. 0 mg kg-1 spinosad, about twice the level that bees would be exposed to in a 'worst case' field scenario, resulting in colony death two to four weeks after initial pesticide exposure. At more realistic concentrations there were potentially important sub-lethal effects. Adult worker bees exposed to spinosad during larval development at 0.8 mg kg(-1) were slower foragers on artificial complex flower arrays than bees from low or no spinosad treated colonies. Inclusion of similar sub-lethal assays to detect effects of pesticides on pollinators would aid in development of environmentally responsible pest management strategies. (c) 2005 Society of Chemical Industry
57. Pernal, SF; Baird, DS; Birmingham, AL; Higo, HA; Slessor, KN; Winston, ML. (2005) Semiochemicals influencing the host-finding behaviour of Varroa destructor.Exp. Appl. Acarol. 37: 1-26 Semiochemicals influencing the host-finding behaviour of Varroa destructor
Apis mellifera; host-finding; Nasonov pheromone; parasite; repellents; semiochemicals; Varroa destructor
Studies of Varroa destructor orientation to honey bees were undertaken to isolate discrete chemical compounds that elicit host-finding activity. Petri dish bioassays were used to study cues that evoked invasion behaviour into simulated brood cells and a Y-tube olfactometer was used to evaluate varroa orientation to olfactory volatiles. In Petri dish bioassays, mites were highly attracted to live L5 worker larvae and to live and freshly freeze-killed nurse bees. Olfactometer bioassays indicated olfactory orientation to the same type of hosts, however mites were not attracted to the odour produced by live pollen foragers. The odour of forager hexane extracts also interfered with the ability of mites to localize and infest a restrained nurse bee host. Varroa mites oriented to the odour produced by newly emerged bees (< 16 h old) when choosing against a clean airstream, however in choices between the odours of newly emerged workers and nurses, mites readily oriented to nurses when newly emerged workers were < 3 h old. The odour produced by newly emerged workers 18-20 h of age was equally as attractive to mites as that of nurse bees, suggesting a changing pro. le of volatiles is produced as newly emerged workers age. Through fractionation and isolation of active components of nurse bee-derived solvent washes, two honey bee Nasonov pheromone components, geraniol and nerolic acid, were shown to confuse mite orientation. We suggest that V. destructor may detect relative concentrations of these compounds in order to discriminate between adult bee hosts, and preferentially parasitize nurse bees over older workers in honey bee colonies. The volatile pro. le of newly emerged worker bees also may serve as an initial stimulus for mites to disperse before being guided by allomonal cues produced by older workers to locate nurses. Fatty acid esters, previously identified as putative kairomones for varroa, proved to be inactive in both types of bioassays. DOI PubMed
56. Slessor, KN; Winston, ML; Le Conte, Y. (2005) Pheromone communication in the honeybee (Apis mellifera L.).J. Chem. Ecol. 31: 2731-2745 Pheromone communication in the honeybee (Apis mellifera L.)
Apis mellifera; honeybee; social insect; chemical communication; pheromone; chemoecology
Recent studies have demonstrated a remarkable and unexpected complexity in social insect pheromone communication, particularly for honeybees (Apis mellifera L.). The intricate interactions characteristic of social insects demand a complex language, based on specialized chemical signals that provide a syntax that is deeper in complexity and richer in nuance than previously imagined. Here, we discuss this rapidly evolving field for honeybees, the only social insect for which any primer pheromones have been identified. Novel research has demonstrated the importance of complexity, synergy, context, and dose, mediated through spatial and temporal pheromone distribution, and has revealed an unprecedented wealth of identified semiochemicals and functions. These new results demand fresh terminology, and we propose adding "colony pheromone" and "passenger pheromone" to the current terms sociochemical, releaser, and primer pheromone to better encompass our growing understanding of chemical communication in social insects. DOI PubMed
55. Birmingham, AL; Hoover, SE; Winston, ML; Ydenberg, RC. (2004) Drifting bumble bee (Hymenoptera : Apidae) workers in commercial greenhouses may be social parasites.Canadian Journal of Zoology-Revue Canadienne de Zoologie 82: 1843-1853 Drifting bumble bee (Hymenoptera : Apidae) workers in commercial greenhouses may be social parasites
Commercial greenhouses require high densities of managed bumble bee (Bombus occidentalis Greene, 1858 and Bombus impatiens Cresson, 1863) colonies to pollinate crops such as tomatoes (Lycopersicon esculentum Miller). We examined drifting, a behavioural consequence of introducing closely aggregated colonies into greenhouse habitats, to determine possible explanations for observed drifting frequencies. Bee drift is normally associated with increased individual mortality and disease transfer between colonies. In this study, individual bees frequently drifted into and remained within foreign colonies. More drifting bees were found in colonies with higher worker and brood populations and greater pollen stores. Increased intracolony aggressive interactions were not associated with a higher number of drifting bees. Drifting bees had a significantly greater number of mature eggs in their ovaries than did resident worker bees residing in colonies hosting drifters, suggesting that drifting could potentially increase the fitness of individual worker bees and may not be solely a function of disorientation and (or) nectar robbing. Taken together, our results suggest that drifting of workers into foreign colonies within greenhouses may demonstrate a predisposition to social parasitism. This selfish worker reproduction challenges our previous understanding of social insect societies as being cooperative societies.
54. Birmingham, AL; Winston, ML. (2004) Orientation and drifting behaviour of bumblebees (Hymenoptera : Apidae) in commercial tomato greenhouses.Canadian Journal of Zoology-Revue Canadienne de Zoologie 82: 52-59 Orientation and drifting behaviour of bumblebees (Hymenoptera : Apidae) in commercial tomato greenhouses
A novel environment lacking in directional cues may present orientation challenges to foraging bees. We examined orientation and drifting behaviour of Bombus occidentalis Greene and Bombus impatiens Cresson, the two major bumblebee pollinators of greenhouse tomatoes in British Columbia. Our objectives were to establish the extent and frequency of bee drift into foreign colonies and to examine the potential of nest entrance patterns and landmarks to reduce drift in commercial greenhouses. On average, 28% of marked bumblebees drifted into foreign hives, making up 0.3%-34.8% of the population in those colonies. Bees drifted towards the top position when hives were vertically stacked. The use of simple black and white patterns and large landmarks did not affect the number of drifting bees, suggesting that disorientation is not a major contributor to drift or to the substantial loss of adult bees from colonies during their first week in a greenhouse. Bees had decreased foraging times when landmarks were present in the greenhouse and showed a marginally but not significantly increased rate of pollen input to colonies. These studies contribute to understanding bumblebee behaviour in a novel environment and determining whether orientation cues are feasible management options to reduce drift and potential bee loss.
53. Franklin, MT; Winston, ML; Morandin, LA. (2004) Effects of clothianidin on Bombus impatiens (Hymenoptera : apidae) colony health and foraging ability.Journal of Economic Entomology 97: 369-373 Effects of clothianidin on Bombus impatiens (Hymenoptera : apidae) colony health and foraging ability
Bombus impatiens; humble bees; clothianidin; chloronicotinyl insecticide; seed dressing
We conducted laboratory experiments to investigate the lethal and sublethal effects of clothianidin on bumble bee, Bombus impatiens Cresson, colony health and foraging ability. Bumble bee colonies were exposed to 6 ppb clothianidin, representing the highest residue levels found in field Studies on pollen, and a higher dose of 36 ppb clothianidin in pollen. Clothianidin did not effect pollen consumption, newly emerged worker weights, amount of brood or the number of workers, males, and queens at either dose. The foraging ability of worker bees tested on an artificial array of complex flowers also did not differ among treatments. These results suggest that clothianidin residues found in seed-treated canola and possibly other crops will not adversely affect the health of humble bee colonies or the foraging ability Of workers.
52. Higo, HA; Rice, ND; Winston, ML; Lewis, B. (2004) Honey bee (Hymenoptera : Apidae) distribution and potential for supplementary pollination in commercial tomato greenhouses during winter.Journal of Economic Entomology 97: 163-170 Honey bee (Hymenoptera : Apidae) distribution and potential for supplementary pollination in commercial tomato greenhouses during winter
Apis mellifera; pollination; greenhouse; tomatoes; bumble bee
This study examined the use of honey bees, Apis mellifera L., to supplement humble bee, Bombus spp., Pollination in commercial tomato, Lycopersicon esculentum Miller, greenhouses in Western Canada. Honey bee colonies were brought into greenhouses already containing humble bees and left for 1 wk to acclimatize. The following week, counts of honey and humble bees foraging and flying throughout the greenhouse were conducted three times per day, and tomato flowers open during honey bee pollination were marked for later fruit harvest. The same counts and flower-marking also were done before and after the presence of honey bees to determine the background level of bumble bee pollination. Overall, tomato size was not affected by the addition of honey bees, but in one greenhouse significantly larger tomatoes were produced with honey bees present compared with humble bees alone. In that greenhouse, honey bee foraging was greater than in the other greenhouses. Honey bees generally foraged within 100 m of their colony in all greenhouses. Our study invites further research to examine the use of honey bees with reduced levels of humble bees, or as sole pollinators of greenhouse tomatoes. We also make specific recommendations for how honey bees can best be managed in greenhouses.
51. Rice, ND; Winston, ML; Higo, HA. (2004) Integrated Pest Management for the parasitic mite Varroa destructor (Anderson and Trueman) in colonies of honey bees (Apis mellifera).American Bee Journal 144: 791-795 Integrated Pest Management for the parasitic mite Varroa destructor (Anderson and Trueman) in colonies of honey bees (Apis mellifera)
Varroa destructor; Apis mellifera; Integrated Pest Management; hygienic queens
The parasitic mite Varroa destructor (Anderson and Trueman) threatens honey bee (Apis mellifera L.) populations world-wide. V destructor are developing resistance to the primary acaricides fluvalinate and coumaphos currently used for control, and the need for alternative management methods is critical. Previous studies have shown that botanical oils, especially thymol, can be effective although variable management tools. Non-chemical control methods also have some effect on V destructor populations when used alone, but the efficacy of these methods when used in combination has not been examined. In this experiment, the single-chemical control systems of 1) Apistan in the spring and fall and 2) thymol-infused florist block in the spring and fall, were compared with a mixed IPM (MIPM) system of 3) thymol in the spring and fall, hygienic bees, and modified bottom boards, and two rotational IPM systems (RIPM) of 4) thymol in the spring and apistan in the fall or 5) Apistan in the spring and thymol in the fall. Adult bee population, brood area, mite population, honey production, and colony loss over the period of the experiment were measured to determine overall colony health and treatment impact. During the 24 months that the IPM experiment was conducted, there were no large differences in adult bee population, brood area and honey production between any of the treatments, although by the end of the experiment replicate numbers were too low to allow for statistical analysis. Colony loss was not significant between treatments. A cost analysis is provided to help beekeepers decide which components of an IPM program may best fit into their colony management schemes.
50. Sabara, HA; Gillespie, DR; Elle, E; Winston, ML. (2004) Influence of brood, vent screening, and time of year on honey bee (Hymenoptera : Apidae) pollination and fruit quality of greenhouse tomatoes.Journal of Economic Entomology 97: 727-734 Influence of brood, vent screening, and time of year on honey bee (Hymenoptera : Apidae) pollination and fruit quality of greenhouse tomatoes
honey bee; Apis mellifera; pollination; greenhouse; tomatoes
Greenhouse tomatoes, Lycopersicon esculentum Miller (Solanaceae), are autogamous, but facilitated pollination results in increased fruit size and set. Previous research examining honey bee pollination in greenhouse tomato crops established that fruit quality resulting from honey bee visitation is often comparable to humble bees (Bombus spp.) and significantly better than in flowers that receive no facilitated pollination. However, management alternatives have not been studied to improve tomato fruit quality when honey bees are the only pollination option available for the high-value greenhouse industry. We investigated whether the quantity of brood (eggs, larvae, and pupae) in a honey bee colony in the winter and screening on greenhouse vents in the summer would encourage honey bee foraging on tomato flowers. We also established the influence of time of year on the potential for honey bees to be effective pollinating agents. We constructed small honey bee colonies full of naive forager bees with either two frames of brood ("brood colonies") or two empty frames ("no-brood") and compared total fruit set and the number of tomato seeds resulting from fruit potentially visited by honey bees in each of these treatments to bagged flowers that received no facilitated pollination. There was no significant difference in the quality of fruit resulting from honey bees from "brood" and "no-brood" colonies. However, these fruits produced significantly more seeds than bagged flowers restricted from facilitated pollination. Honey bees from brood and no-brood colonies also resulted in 98% fruit set compared with 80% fruit set in bagged flowers that received no facilitated pollination. During the summer, the number of seeds per fruit did not differ significantly between unbagged flowers potentially visited by honey bees in screened greenhouses and unscreened greenhouses and bagged flowers that received no facilitated pollination. However, time of year did have a significant influence on the quality of fruit produced by honey bees compared with flowers that received no facilitated pollination, because no difference in seed number was observed between the treatments after mid-April. The results from this study demonstrate that the management of brood levels and vent screening cannot be used to improve the quality of fruit resulting from honey bee pollination and that honey bees can be a feasible greenhouse pollination alternative only during the winter. DOI
49. Tommasi, D; Miro, A; Higo, HA; Winston, ML. (2004) Bee diversity and abundance in an urban setting.Canadian Entomologist 136: 851-869 Bee diversity and abundance in an urban setting
We assessed bee diversity and abundance in urban areas of Vancouver, British Columbia, Canada, to determine how urban environments can support bees. Habitats examined were community and botanical gardens, urban wild areas, Naturescape flower beds and backyards, and traditional flower beds and backyards. A total of 56 bee species (Hymenoptera), including species of the genera Andrena Fabr. (Andrenidae), Bombus Latr. (Apidae), Osmia Panzer and Megachile Latr. (Megachilidae), and Halictus Latr. and Dialictus Pauly (Halictidae), were collected. Abundance exhibited strong seasonal variation. Wild bees were most abundant during late spring, whereas honey bees peaked at the end of the summer. The most abundant species seen was the managed honey bee Apis mellifera L. (Apidae), followed by wild Bombus flavifrons Cresson. Community and botanical gardens, and plants such as cotoneaster (Cotoneaster Medik. sp.) and blackberry (Rubus discolor Weihe & Nees) (Rosaceae), centaurea (Centaurea L. sp.; Asteraceae), buttercup (Ranunculus L. sp.; Ranunculaceae), and foxglove (Digitalis L. sp.; Scrophulariaceae), had the highest abundance of bees, while bee populations in wild areas were the most diverse. Weeds such as dandelions (Taraxacum officinale G.H. Weber ex Wiggers; Asteraceae) dominated these wild areas and had one of the highest diversities of bee visitors. Traditional flower beds with tulips (Tulipa L. sp.; Liliaceae) and petunias (Petunia Juss. sp.; Solanaceae) had relatively poor diversity and abundance of bees throughout the year. Our study suggests that urban areas have the potential to be important pollinator reservoirs, especially if both bloom and habitat heterogeneity are maintained and enhanced through sustainable urban planning.
48. Whittington, R; Winston, ML. (2004) Comparison and examination of Bombus occidentalis and Bombus impatiens (Hymenoptera : Apidae) in tomato greenhouses.Journal of Economic Entomology 97: 1384-1389 Comparison and examination of Bombus occidentalis and Bombus impatiens (Hymenoptera : Apidae) in tomato greenhouses
Bombus; bumble bee; population; foraging effort; tomato
Experiments were conducted in commercial tomato, Lycopersicon esculentum Miller (Solanaceae), greenhouses to compare the relative foraging effort of two bumble bee species, Bombus occidentalis Greene and Bombus impatiens Cresson, to examine interspecific competition between B. occidentalis and B, impatiens, and to determine whether humble bee colonies grew to their full population potential in commercial tomato greenhouses. B. impatiens colonies had more brood and workers and made more foraging trips per hour than B. occidentalis colonies. However, B. impatiens returned to the colony without pollen loads and left their colonies without dropping off their pollen loads more frequently than B. occidentalis greenhouse colonies. Our data also suggest that the presence of B. impatiens had a detrimental effect on B. occidentalis populations. Furthermore, B. occidentalis colonies did not grow to their full population potential in tomato greenhouses, with fewer workers in greenhouse colonies than in colonies placed outside in a natural environment, or in colonies that were physically enclosed and protected from external mortality. Together, this study suggests that B. impatiens is a better pollinator than B. occidentalis. It also shows that unknown factors are limiting the size of B. occidentalis colonies in tomato greenhouses.
47. Whittington, R; Winston, ML; Tucker, C; Parachnowitsch, AL. (2004) Plant-species identity of pollen collected by bumblebees placed in greenhouses for tomato pollination.Canadian Journal of Plant Science 84: 599-602 Plant-species identity of pollen collected by bumblebees placed in greenhouses for tomato pollination
bumblebee; Bombus occidentalis; Bombus impatiens; pollen; greenhouse; tomato
The seasonal variation of pollen collected from different plant species by greenhouse bumblebees was investigated to determine how frequently bumblebees forage outside of commercial tomato greenhouses. Pollen was collected from bumblebees at three greenhouses between February and September 2001 and the plant species identity of pollen collected was determined with light microscopy. A significant amount of non-tomato pollen was collected by bumblebees during. one or more months from outside each of the three greenhouses studied. The bees brought black as little as an average of 5% non-tomato pollen between February and September at one greenhouse and as much as 73% during July at another. Therefore, greenhouse, tomato growers are probably not obtaining maximum pollination benefit from bumblebee colonies and should address methods to reduce their foraging outside the greenhouse.
46. Hoover, SER; Keeling, CI; Winston, ML; Slessor, KN. (2003) The effect of queen pheromones on worker honey bee ovary development.Naturwissenschaften 90: 477-480 The effect of queen pheromones on worker honey bee ovary development
We report results that address a long-standing controversy in honey bee biology, the identity of the queen-produced compounds that inhibit worker honey bee ovary development. As the honey bee is the only organism for which identities have been proposed for any pheromone that regulates reproduction, the resolution of its identity is of broad significance. We examined the effects of synthetic honey bee queen mandibular pheromone (QMP), four newly identified queen retinue pheromone components, and whole-queen extracts on the ovary development of caged worker bees. The newly identified compounds did not inhibit worker ovary development alone, nor did they improve the efficacy of QMP when applied in combination. QMP was as effective as queen extracts at ovary regulation. Caged workers in the QMP and queen extract treatments had better developed ovaries than did workers remaining in queenright colonies. We conclude that QMP is responsible for the ovary-regulating pheromonal capability of queens from European-derived Apis mellifera subspecies. DOI PubMed
45. Keeling, CI; Slessor, KN; Higo, HA; Winston, ML. (2003) New components of the honey bee (Apis mellifera L.) queen retinue pheromone.Proc. Natl. Acad. Sci. U. S. A. 100: 4486-4491 New components of the honey bee (Apis mellifera L.) queen retinue pheromone
The honey bee queen produces pheromones that function in both releaser and primer roles such as attracting a retinue of workers around her, attracting drones on mating flights, preventing workers from reproducing at the individual (worker egg-laying) and colony (swarming) level, and regulating several other aspects of colony functioning. The queen mandibular pheromone (QMP), consisting of five synergistic components, is the only pheromone chemically identified in the honey bee (Apis mellifera L.) queen, but this pheromone does not fully duplicate the pheromonal activity of a full queen extract. To identify the remaining unknown compounds for retinue attraction, honey bee colonies were selectively bred to have low response to synthetic QMP and high response to a queen extract in a laboratory retinue bioassay. Workers from these colonies were then used in the bioassay to guide the isolation and identification of the remaining active components. Four new compounds were identified from several glandular sources that account for the majority of the difference in retinue attraction between synthetic QMP and queen extract: methyl (Z)-octadec-9-enoate (methyl oleate), (E)-3-(4-hydroxy-3-methoxyphenyl)-prop-2-en-1-ol (coniferyl alcohol), hexadecan-1-ol, and (Z9,Z12,Z15)-octadeca-9,12,15-trienoic acid (linolenic acid). These compounds were inactive alone or in combination, and they only elicited attraction in the presence of QMP. There was still unidentified activity remaining in the queen extract. The queen therefore produces a synergistic, multiglandular pheromone blend of at least nine compounds for retinue attraction, the most complex pheromone blend known for inducing a single behavior in any organism. DOI PubMed
44. Morandin, LA; Winston, ML. (2003) Effects of novel pesticides on bumble bee (Hymenoptera : Apidae) colony health and foraging ability.Environmental Entomology 32: 555-563 Effects of novel pesticides on bumble bee (Hymenoptera : Apidae) colony health and foraging ability
bumble bees; Bombus occidentalis; B. impatiens; nontarget insects; genetically modified; insecticides
Two experiments were conducted testing for lethal and sublethal effects of the transgenic proteins Cry1Ac and chitinase, and the chemical seed and soil treatment imidacloprid on humble bees (Bombus occidentalis Greene and B. impatiens Cresson, Hymenoptera: Apidae). In the first experiment, B. occidentalis colonies were exposed to realistic residue levels of Cry1Ac, chitinase, and imidacloprid found in pollen. There were no effects on pollen consumption, bumble bee worker weights, colony size, amount of brood, or the number of queens and males produced. In the second experiment, using B. impatiens, we tested the effects of Cry1Ac and two levels of imidacloprid. Similar colony health measures were collected as in the first experiment, but in addition foraging ability of individual bees was tested on complex artificial flowers. There were no differences in colony characteristics among treatments. However, bees in the high-imidacloprid treatment had longer handling times on the complex flowers than bees in the other treatments. No lethal, sublethal colony, or individual foraging effects of these novel pesticides were found at residue levels found in the field, suggesting that humble bee colonies will not be harmed by proper use of these pesticides. Use of an artificial flower foraging array proved to be a sensitive method for detecting sublethal response of bees to pesticides.
43. Sabara, HA; Winston, ML. (2003) Managing honey bees (Hymenoptera : Apidae) for greenhouse tomato pollination.Journal of Economic Entomology 96: 547-554 Managing honey bees (Hymenoptera : Apidae) for greenhouse tomato pollination
honey bee; Apis mellifera; pollination; greenhouse; tomatoes; colony management
Although commercially reared colonies of humble bees (Bombus sp.) are the primary pollinator world-wide for greenhouse tomatoes (Lycopersicon esculentum Mill.) previous research indicates that honey bees (Apis mellifera L.) might be a feasible alternative or supplement to bumble bee pollination. However, management methods for honey bee greenhouse tomato pollination scarcely have been explored. We 1) tested the effect of initial amounts of brood on colony population size and flight activity in screened greenhouses during the winter, and 2) compared foraging from colonies with brood used within screened and unscreened greenhouses during the summer. Brood rearing was maintained at low levels in both brood and no-brood colonies after 21 d during the winter, and emerging honey bees from both treatments bad significantly lower weights than bees from outdoor colonies. Honey bee flight activity throughout the day and over the 21 d in the greenhouse was not influenced by initial brood level. In our summer experiment, brood production in screened greenhouses neared zero after 21 d but higher levels of brood were reared in unscreened greenhouses with access to outside forage. Flower visitation measured throughout the day and over the 21 d the colonies were in the greenhouse was not influenced by screening treatment. An economic analysis indicated that managing honey bees for greenhouse tomato pollination would be financially viable for both beekeepers and growers. We conclude that honey bees can be successfully managed for greenhouse tomato pollination in both screened and unscreened greenhouses if the foraging force is maintained by replacing colonies every 3 wk.
42. Whittington, R; Winston, ML. (2003) Are bumble bee colonies in tomato greenhouses obtaining adequate nutrition?Canadian Entomologist 135: 883-892 Are bumble bee colonies in tomato greenhouses obtaining adequate nutrition?
Managed bumble bees are important pollinators of greenhouse crops, but few studies have examined factors that affect the health and productivity of commercially produced colonies. We investigated whether supplemental feeding with diverse pollens affected worker longevity and colony size of Bombus occidentalis Greene (Hymenoptera: Apidae) colonies in tomato (Solanaceae) greenhouses. We found no differences in colony worker populations, brood production, or queen and drone production between supplemented and nonsupplemented treatments, suggesting that B. occidentalis colonies obtain adequate nutrition from the tomato pollen available in greenhouses. Adult populations did not increase in any treatment, but either remained stable or declined after colonies were placed in greenhouses. Because brood-rearing increased in all treatments but adult populations did not, adult mortality due to a non-nutritional factor such as disease or disorientation appears to be an important problem limiting the size of bumble bee colonies, and thus the effectiveness of bumble bees for greenhouse tomato pollination.
41. Whittington, R; Winston, ML. (2003) Effects of Nosema bombi and its treatment fumagillin on bumble bee (Bombus occidentalis) colonies.Journal of Invertebrate Pathology 84: 54-58 Effects of Nosema bombi and its treatment fumagillin on bumble bee (Bombus occidentalis) colonies
Bombus occidentalis; bumble bee; Nosema bombi; fumagillin; antibiotic; greenhouse
We examined the effects of Nosema bombi (Microsporidia: Nosematidae) on colonies of bumble bees, Bombus occidentalis Greene (Hymenoptera: Apidae), used to pollinate tomatoes in commercial greenhouses. We assessed methods of detecting N. bombi and tested the effectiveness of fumagillin to control this parasite. N. bombi did not affect adult population size or amount of brood in B. occidentalis colonies. Fumagillin was not effective against N. bombi at the doses we tested, and frass samples did not provide accurate estimates of the intensity of N. bombi infections. The number of N. bombi spores per bee was highly variable among bumble bees within colonies, and accurate estimates could only be obtained by sampling a large proportion of bees in each colony. Therefore, whole bee and frass sampling is useful for determining if N. bombi is present or absent, but not for obtaining accurate estimates of the intensity of N. bombi infections. (C) 2003 Elsevier Inc. All rights reserved.
40.Winston, M. (2003) Bees and biotechnology.Bee World 84: 141-143 Bees and biotechnology
Public debates about genetically modified crops have been riveting. We know that the implications of applying biotechnology to agriculture are profound, but societal consensus eludes us. The extreme rhetoric that has surrounded GM crops has created a chaotic array of misinformation, rumour and value judgements that has made it difficult for the public to reach even a majority opinion about the benefits and risks of these new technologies.
39. Rice, ND; Winston, ML; Whittington, R; Higo, HA. (2002) Comparison of release mechanisms for botanical oils to control Varroa destructor (Acari : Varroidae) and Acarapis woodi (Acari : Tarsonemidae) in colonies of honey bees (Hymenoptera : Apidae).Journal of Economic Entomology 95: 221-226 Comparison of release mechanisms for botanical oils to control Varroa destructor (Acari : Varroidae) and Acarapis woodi (Acari : Tarsonemidae) in colonies of honey bees (Hymenoptera : Apidae)
honey bee; Varroa destructor; Acarapis woodi; botanical oil; thymol
Two major parasitic pests threaten honey bee populations, the external mite Varroa destructor and the internal mite Acarapis woodi (Rennie). Varroa are beginning to develop resistance to the main chemical defense fluvalinate, and alternative control methods are being pursued. Previous studies have shown that botanical oils, especially thymol, can be effective. Six release devices for either thymol or a blend of botanical oils known as Magic 3 were tested in beehives. The release devices were as follows: (1) low density polyethylene (LDPE) sleeves filled with Magic 3, (2) Magic 3-infused florist blocks, (3) thymol infused florist blocks, (4) a canola oil and thymol mixture wick release, (5) a plastic strip coated with calcium carbonate and Magic 3, and (6) an untreated control. There were significant decreases in varroa levels with the use of Magic 3 sleeves, but brood levels also decreased. Tracheal mite levels significantly decreased with the Magic 3 sleeve treatment, the Magic 3 florist block treatment, and the thymol canola wick treatment. A second experiment showed that changing the location of Magic 3 sleeves in the colony did not detrimentally effect.brood levels, but also did not effectively control varroa mites.
38. Downey, DL; Winston, ML. (2001) Honey bee colony mortality and productivity with single and dual infestations of parasitic mite species.Apidologie 32: 567-575 Honey bee colony mortality and productivity with single and dual infestations of parasitic mite species
Varroa destructor; Acarapis woodi; colony productivity; colony mortality
Colony mortality and productivity were compared between honey bee (Apis mellifera) colonies infested by zero, one or both species of parasitic mites (Acarapis woodi or Varroa destructor). Mortality, bee and mite populations, sealed brood, and stores were monitored for 16 months, beginning in May. By the following March, 5 out of 6 colonies with both mites were dead, but no other colonies died until September, when 3 out of 4 V. destructor colonies were dead. Dually infested colonies initially had more honey stores, but were dead by March. At that point V. destructor colonies had significantly less worker brood, fewer adult bees and more honey than colonies with no mites or tracheal mites (Acarapis woodi). The colonies with tracheal mites (n = 9) and no mites (n = 8) did not differ in any productivity parameter measured. These results suggest a synergistic interaction between tracheal and V. destructor mites, treatments against tracheal mites should be applied in dually infested colonies, even if tracheal mites alone are not having an impact.
37. Ledoux, MN; Winston, ML; Higo, H; Keeling, CI; Slessor, KN; Le Conte, Y. (2001) Queen pheromonal factors influencing comb construction by simulated honey bee (Apis mellifera L.) swarms.Insect. Soc. 48: 14-20 Queen pheromonal factors influencing comb construction by simulated honey bee (Apis mellifera L.) swarms
Apidae; honey bees; Apis mellifera; queen mandibular pheromone; comb construction
The influence of the queen and her pheromonal signal on comb construction was examined. We tested four treatments with newly hived packages of bees containing: 1) a mated queen, 2) a virgin queen, 3) no queen but with a dispenser containing synthetic queen mandibular pheromone (QMP), and 4) no queen and no pheromone. After 10 days, the comb produced by each colony was removed, comb measurements made, bees from the comb-building area collected the size of the scales on the wax mirrors of the collected bees ranked on a scale of 0-4 and the queens removed and analyzed for QMP components. Queenless workers built substantially less comb and the comb they did build had significantly larger, drone-sized cells than for the other 3 treatments, indicating that both cell size and the quantity of comb built are mediated through the queen, particularly QMP. The observations of wax scale size suggested that QMP influenced comb building behaviour rather than wax scale production. These results support the idea that queenless honey bees can adopt a strategy of constructing drone-sized cells in order to increase reproductive fitness through male production following queen loss. DOI
36. Dogterom, MH; Winston, ML; Mukai, A. (2000) Effect of pollen load size and source (self, outcross) on seed and fruit production in highbush blueberry cv. 'Bluecrop' (Vaccinium corymbosum; Ericaceae).American Journal of Botany 87: 1584-1591 Effect of pollen load size and source (self, outcross) on seed and fruit production in highbush blueberry cv. 'Bluecrop' (Vaccinium corymbosum; Ericaceae)
blueberry; Ericaceae; fruit; germination; highbush; outcross; pollen; seed; selfing; Vaccinium
Reproductive fitness of a plant is ultimately determined by both number and quality of seed offspring. This is determined by sexual selection of pollen microspores and ovules during pollination and fertilization. These processes may include pollen competition and seed abortion, which reduce the number of microspores and ovules available for final seed production. Thus. even an excess of pollen microspores to ovules does nor result in fertile seeds equal to ovule number. We investigated pollen requirements of highbush blueberry (Vaccinium corymbosum cultivar 'Bluecrop') for maximal seed production and how fertile seed number translates into fruit quality, since fruit quality would ultimately determine the dispersal of its offspring. We demonstrate that individual blueberry flowers with a mean of 106 ovules reach their maximum fruit set and mass and minimum time to ripen when 125 outcross pollen tetrads pollinate a flower, compared to 10 or 25. Three hundred tetrads resulted in the increase of fertile seeds, but did not result in a further increase of fruit mass or fruit set, or decrease in time to ripen. We also examined the effect of pure and mixed loads Of Self and outcross pollen (25 and 125 tetrads), and found no differences in fertile seed number, fruit mass, or percentage fruit set when pollen lends were either 25 self or outcross pollen tetrads, although number of days to ripen was significantly shorter by 8 d with 25 outcross tetrads. When the pollen load of 125 tetrads consisted of self or a 50:50 mixture of self and outcross pollen, fruit mass, days to ripen, and percentage fruit set were not different from lends of 125 outcross pollen. In addition, a pollen load of 25 outcross tetrads resulted in fertile seed number and fruit quality in between that of 25 self, and 125 self 125 mixed, or 125 outcross tetrads. Large, small, and flat seed types were identified, and only large seeds (length = 1.7 mm) were fertile. These results improve our understanding of pollen load size and source requirements of a crop plant and the limits to pollen transfer when translated to fruit growth.
35. Downey, DL; Higo, TT; Winston, ML. (2000) Single and dual parasitic mite infestations on the honey bee, Apis mellifera L.Insectes Sociaux 47: 171-176 Single and dual parasitic mite infestations on the honey bee, Apis mellifera L.
Varroa jacobsoni; Acarapis woodi; colony state; foraging behavior; host selection
The onset of foraging, proportion of pollen collectors, and weight of pollen loads were compared in individual honey bees (Apis mellifera) infested by zero, one (Acarapis woodi, the honey bee tracheal mite, or Varroa jacobsoni,varroa), or both species of parasitic mites. Phoretic varroa host choice also was compared between bees with and without tracheal mites, and tracheal mite infestation of hosts was compared between bees parasitized or not by varroa during development. The proportion of pollen collectors was not significantly different between treatments, but bees parasitized by both mites had significantly smaller pollen loads than uninfested bees. Mean onset of foraging was earliest for bees parasitized by varroa during development, 15.9 days. Bees with tracheal mites began foraging latest, at 20.5 days, and foraging ages were intermediate in bees with no mites and both, 17.6 and 18.0 days respectively. Phoretic varroa were found equally on bees with and without tracheal mite infestations, but bees parasitized by varroa during development were almost twice as likely to have tracheal mite infestations as bees with no varroa parasitism, 63.9% and 35.5%, respectively. These results indicate that these two parasites can have a biological interaction at the level of individual bees that is detrimental to their host colonies.
34. Janmaat, AF; Winston, ML. (2000) Removal of Varroa jacobsoni infested brood in honey bee colonies with differing pollen stores.Apidologie 31: 377-385 Removal of Varroa jacobsoni infested brood in honey bee colonies with differing pollen stores
Varroa jacobsoni; honey bee; pollen; brood removal
The effects of high or low pollen storage on Apis mellifera L. brood removal behavior and Varuoa jacobsoni reproduction were examined. High pollen storage colonies removed 49% of the infested larvae compared to 33% removal by the low pollen storage colonies. No difference was found in the proportion of fertile mites between those reared in high or low pollen storage colonies, although mite fertility appeared to decrease from mid to late summer in British Columbia, Canada. These findings indicate that the presence of pollen stores increases the rate of cell removal, and warrants further investigation into colony management as a potential means of V. jacobsoni infestation control.
33. Janmaat, AF; Winston, ML. (2000) The influence of pollen storage area and Varroa jacobsoni Oudemans parasitism on temporal caste structure in honey bees (Apis mellifera L.).Insectes Sociaux 47: 177-182 The influence of pollen storage area and Varroa jacobsoni Oudemans parasitism on temporal caste structure in honey bees (Apis mellifera L.)
Varroa jacobsoni; pollen; honey bees; Apis mellifera; temporal polyethism
The influence of colony pollen storage and pupal infestation by the parasitic mite Varroa jacobsoni on worker longevity, foraging age, and behavior were investigated in the honey bee, Apis mellifera L. Workers reared in colonies with low pollen stores began foraging at younger ages and may have had shorter lifespans than workers reared in colonies with high pollen availability. Similarly, workers began foraging at younger ages and had shorter lifespans when they had been infested by V. jacobsoni as pupae. The decrease in foraging age and possibly lifespan caused by the pupal infestation was offset by the colony's pollen environment during brood rearing. Therefore, temporal task schedules are affected by both colony investment and parasitism by V. jacobsoni during brood rearing.
32. Janmaat, AF; Winston, ML; Ydenberg, RC. (2000) Condition-dependent response to changes in pollen stores by honey bee (Apis mellifera) colonies with different parasitic loads.Behavioral Ecology and Sociobiology 47: 171-179 Condition-dependent response to changes in pollen stores by honey bee (Apis mellifera) colonies with different parasitic loads
honey bee; Varroa jacobsoni; pollen foraging; parasitism; efficiency
The impact of a parasitic infestation may be influenced by nutritional state, in both individuals and colonies. This study examined the interaction between pollen storage and the effects of an infestation by the mite, Varroa jacobsoni Oudemans, in colonies of the honey bee, Apis mellifera L. We manipulated the pollen storage and mite infestation levels of colonies, and measured pollen foraging and brood rearing. Increased pollen stores decreased both the number of pollen foragers and pollen load size, while initially at least foragers from colonies with moderate infestations carried smaller pollen loads than those from lightly infested colonies. Over the course of the experiment, all colonies significantly increased pollen-foraging rates and pollen consumption, which was presumably a seasonal effect. Lightly infested colonies exhibited a larger increase in pollen forager number than moderately infested colonies, suggesting that more intense mite infestations compromised forager recruitment. Brood production was not affected by the addition of pollen, but moderately infested colonies were rearing significantly less brood by the end of the experiment than lightly infested colonies. Furthermore, the efficiency with which colonies converted pollen to brood decreased as the pollen storage level decreased and the infestation level increased. The results of this study may indicate that honey bee colonies adaptively alter brood-production efficiency in response to parasitic infestations and seasonal changes.
31. LeDoux, MN; Pernal, SF; Higo, HA; Winston, ML. (2000) Development of a bioassay to test the orientation behaviour of the honey bee ectoparasite, Varroa jacobsoni.Journal of Apicultural Research 39: 47-54 Development of a bioassay to test the orientation behaviour of the honey bee ectoparasite, Varroa jacobsoni
worker honey bees; Apis mellifera; Varroa jacobsoni; mites; orientation behaviour; olfactory stimulation; bioassay; larvae; nurse bees; extraction
A bioassay was developed to test various aspects of the orientation behaviour of the honey bee ectoparasite, Varroa jacobsoni. The bioassay arena consisted of a petri dish, 60 mm in diameter, in which live honey bee larvae and previously frozen adults were used as hosts. Bioassays were conducted in a dark incubator at 32 degrees C for 60 min. Greater numbers of mites parasitized worker larvae than drone larvae, but this trend was not significant. Mites of various ages given a choice between nurse bees and fifth instar worker larvae preferred nurse bees at all ages of mites tested, excluding newly emerged mites. When given a choice between a nurse bee and a pollen forager, V. jacobsoni did not show a preference, and similarly when given a choice between a nurse bee and an adult drone no preference was observed. Finally, when given a choice between a nurse bee extracted with hexane and a non-extracted nurse bee, V. jacobsoni preferred the nonextracted host.
30. Lindberg, CM; Melathopoulos, AP; Winston, ML. (2000) Laboratory evaluation of miticides to control Varroa jacobsoni (Acari : Varroidae), a honey bee (Hymenoptera : Apidae) parasite.Journal of Economic Entomology 93: 189-198 Laboratory evaluation of miticides to control Varroa jacobsoni (Acari : Varroidae), a honey bee (Hymenoptera : Apidae) parasite
Apis mellifera; Varroa jacobsoni; bioassay; essential oils; tau-fluvalinate
A laboratory bioassay was developed to evaluate miticides to control Varroa jacobsoni (Oudemans), an important parasite of the honey bee, Apis mellifera L. Bees and mites were exposed to applications of essential oil constituents in petri dishes (60 by 20 mm). The registered mite control agents tau-fluvalinate (Apistan) and formic acid also were evaluated as positive controls. Treatments that caused high mite mortality (>70%) at doses that produced low bee mortality ((30%) were considered mite selective. The six most selective of the 22 treatments tested (clove oil, benzyl acetate, thymol, carvacrol, methyl salicylate, and Magic3) were further evaluated to estimate LDS, values and selectivity ratios (A. mellifera LD50/V. jacobsoni LD50) at 24, 43, and 67 h after exposure. Tau-fluvalinate was the most selective treatment, hut thymol, clove oil, Magic3, and methyl salicylate demonstrated selectivity equal to or greater than formic acid. The effect of mode of application (complete exposure versus vapor only) on bee and mite mortality was assessed for thymol, clove oil, and Magic3 by using a 2-chambered dish design. Estimated V. Jacobsoni LD50 values were significantly lower for complete exposure applications of thymol and Magic3 suggesting that both vapor and topical exposure influenced mite mortality, whereas estimated values for clove oil suggested that topical exposure had little or no influence on mite mortality. These results indicate that essential oil constituents alone may not be selective enough to control Varroa under all conditions, but could be a useful component of an integrated pest management approach to parasitic mite management in honey bee colonies.
29. Melathopoulos, AP; Winston, ML; Whittington, R; Higo, H; Le Doux, M. (2000) Field evaluation of neem and Canola oil for the selective control of the honey bee (Hymenoptera : Apidae) mite parasites Varroa jacobsoni (Acari : Varroidae) and Acarapis woodi (Acari : Tarsonemidae).Journal of Economic Entomology 93: 559-567 Field evaluation of neem and Canola oil for the selective control of the honey bee (Hymenoptera : Apidae) mite parasites Varroa jacobsoni (Acari : Varroidae) and Acarapis woodi (Acari : Tarsonemidae)
Varroa jacobsoni; Acarapis woodi; Acaricide; mite; neem; canola oil
Neem oil, neem extract (neem-aza), and canola oil were evaluated for the management of the honey bee mite parasites Varroa jacobsoni (Oudemans) and Acarapis woodi (Rennie) in field experiments. Spraying neem oil on bees was more effective at controlling V. jacobsoni than feeding oil in a sucrose-based matrix (patty),feeding neem-aza in syrup, or spraying canola oil. Neem oil sprays also protected susceptible bees from A. woodi infestation. Only neem oil provided V. jacobsoni control comparable to the known varroacide formic acid, but it was not as effective as the synthetic product Apistan (tau-fluvalinate). Neem oil was effective only when sprayed six times at 4-d intervals and not when applied three times at 8-d intervals. Neem oil spray treatments had no effect on adult honey bee populations, but treatments reduced the amount of sealed brood in colonies by 50% and caused queen loss at higher doses. Taken together, the results suggest that neem and canola oil show some promise for managing honey bee parasitic mites, but the negative effects of treatments to colonies and the lower efficacy against V. jacobsoni compared with synthetic acaricides may limit their usefulness to beekeepers.
28. Melathopoulos, AP; Winston, ML; Whittington, R; Smith, T; Lindberg, C; Mukai, A; Moore, M. (2000) Comparative laboratory toxicity of neem pesticides to honey bees (Hymenoptera : Apidae), their mite parasites Varroa jacobsoni (Acari : Varroidae) and Acarapis woodi (Acari : Tarsonemidae), and brood pathogens Paenibacillus larvae and Ascophaera apis.Journal of Economic Entomology 93: 199-209 Comparative laboratory toxicity of neem pesticides to honey bees (Hymenoptera : Apidae), their mite parasites Varroa jacobsoni (Acari : Varroidae) and Acarapis woodi (Acari : Tarsonemidae), and brood pathogens Paenibacillus larvae and Ascophaera apis
Varroa; Acarapis; acaricide; bioassay; neem; oil; tau-fluvalinate
Laboratory bioassays were conducted to evaluate neem oil and neem extract for the management of key honey bee (Apis mellifera L.) pests. Neem pesticides inhibited the growth of Paenibacillus larvae (Ash, Priest & Collins) in vitro but had no effect on the growth of Ascophaera al,is (Olive & Spiltoir). Azadirachtin-rich extract (neem-aza) was 10 times more potent than crude neem oil (neem oil) against P. larvae suggesting that azadirachtin is a main antibiotic component in neem. Neem-aza, however, was ineffective at controlling the honey bee mite parasites Varroa jacobsoni (Ouduemans) and Acarapis woodi (Rennie). Honey bees also were deterred from feeding on sucrose syrup containing >0.01 mg/ml of neem-aza. However, neem oil applied topically to infested bees in the laboratory proved highly effective against both mite species. Approximately 50-90% V. jacobsoni mortality was observed 48 h after treatment with associated bee mortality lower than 10%. Although topically applied neem oil did not result in direct A. woodi mortality, it offered significant protection of bees from infestation by A. woodi. Other vegetable and petroleum-based oils also offered selective control of honey bee mites, suggesting neem oil has both a physical and a toxicological mode of action. Although oils are not as selective as the V. Jacobsoni acaricide tau-fluvalinate, they nonetheless hold promise for the simultaneous management of several honey bee pests.
27. Pankiw, T; Winston, ML; Fondrk, MK; Slessor, KN. (2000) Selection on worker honeybee responses to queen pheromone (Apis mellifera L.).Naturwissenschaften 87: 487-490 Selection on worker honeybee responses to queen pheromone (Apis mellifera L.)
Disruptive selection for responsiveness to queen mandibular gland pheromone (QMP) in the retinue bioassay resulted in the production of high and low QMP responding strains of honeybees (Apis mellifera L.), Strains differed significantly in their retinue response to QMP after one generation of selection. By the third generation the high strain was on average at least nine times more responsive than the low strain, The strains showed seasonal phenotypic plasticity such that both strains were more responsive to the pheromone in the spring than in the fall. Directional selection for low seasonal variation indicated that phenotypic plasticity was an additional genetic component to retinue response to QMP. Selection for high and low retinue responsiveness to QMP was not an artifact of the synthetic blend because both strains were equally responsive or non-responsive to whole mandibular gland extracts compared with QMP. The use of these strains clearly pointed to an extra-mandibular source of retinue pheromones (Pankiw et al. 1995; Slessor et al. 1998; Keeling et al. 1999). DOI PubMed
26. Whittington, R; Winston, ML; Melathopoulos, AP; Higo, HA. (2000) Evaluation of the botanical oils neem, thymol, and canola sprayed to control Varroa jacobsoni Oud.(Acari : Varroidae) and Acarapis woodi (Acari : Tarsonemidae) in colonies of honey bees (Apis mellifera L., Hymenoptera : Apidae).American Bee Journal 140: 567-572 Evaluation of the botanical oils neem, thymol, and canola sprayed to control Varroa jacobsoni Oud.(Acari : Varroidae) and Acarapis woodi (Acari : Tarsonemidae) in colonies of honey bees (Apis mellifera L., Hymenoptera : Apidae)
Apis mellifera; Varroa jacobsoni; Acarapis woodi; acaricide; neem; thymol; canola oil
The botanical oils neem, thymol, and canola were examined for control of parasitic mites (Varroa jacobsoni and Acarapis woodi) in honey bee (Apis mellifera) colonies. Neem oil spray (5% solution) killed 90 +/- 6% of varroa mites, three times more than died in the untreated group. Thymol-oil spray (4.8g thymol/L in 20% canola oil solution), thymol in vermiculite (3.6g/vermiculite block), and canola oil spray (20% solution) killed 79 +/- 8%, 68 +/- 6%, and 65 +/- 6% of the varroa mites, respectively. Colonies treated with the thymol-oil spray had a significantly lower tracheal mite infestation (1.3 +/- 7.5%) at the end of the treatment period than the untreated group (23.3 +/- 6.0%). All other treatments showed a slight but not statistically significant decrease in tracheal mite infestation levels, Neem and thymol-oil spray treatments were detrimental to bees, as they both had 50% queen loss, and colonies treated with neem oil had one-third as many adult bees and one-sixth as much brood as untreated colonies at the end of the experiment. However, both neem and thymol-oil spray treatments were as effective as commercially available formic acid against varroa mites. The negative effects on bees may be remedied by changes in formulation, application technology, and season of application, Neem, thymol, and canola oil treatments provide adequate control of varroa mites to be useful in an integrated pest management approach. These natural products may have the added advantage of simultaneously reducing tracheal mite populations. Thus, continued research to develop application methods that do not cause bee mortality is warranted.
25. Dogterom, MH; Winston, ML. (1999) Pollen storage and foraging by honey bees (Hymenoptera : Apidae) in highbush blueberries (Ericaceae), cultivar bluecrop.Canadian Entomologist 131: 757-768 Pollen storage and foraging by honey bees (Hymenoptera : Apidae) in highbush blueberries (Ericaceae), cultivar bluecrop
We investigated pollen and nectar foraging of honey bees, Apis mellifera L., from pollen-poor and pollen-rich, small and large colonies in blooming highbush blueberry, Vaccinium corymbosum L. cv. Bluecrop fields. The proportion of pollen foragers differed significantly between pollen-rich and pollen-poor colonies after storage levels were manipulated, but foraging and pollen stores returned to similar levels within a week. No differences were found in small colonies, although the proportion of pollen foragers was high (46% and 45% from pollen-rich and pollen-poor colonies, respectively). Only 7.6% of pollen foragers carried Vaccinium sp. pollen in their loads independent of treatment, day, and colony size, whereas 60.8% of nectar foragers carried up to 100 tetrads of Vaccinium sp. pollen on their bodies. The average proportion of Vaccinium sp. pollen carried by nectar and pollen foragers per day and treatment was less than 10%. Our research indicates that when colonies are placed in fields of blooming blueberry flowers, pollen foraging is stimulated in large colonies with stores that are pollen poor, but predominantly for pollen types other than blueberry. This research indicates that nectar foragers are the major visitor of highbush blueberry cv. Bluecrop and suggests that increasing the number of nectar foragers rather than pollen foragers would result in more honey bees foraging on highbush blueberry, in particular cv. Bluecrop.
24. Lin, HR; Winston, ML; Haunerland, NH; Slessor, KN. (1999) Influence of age and population size on ovarian development, and of trophallaxis on ovarian development and vitellogenin titres of queenless worker honey bee (Hymenoptera : Apidae).Can. Entomol. 131: 695-706 Influence of age and population size on ovarian development, and of trophallaxis on ovarian development and vitellogenin titres of queenless worker honey bee (Hymenoptera : Apidae)
We examined the factors that might influence ovary development in worker honey bees, Apis mellifera L. Queenless workers at different ages (less than or equal to 12 h, and 4, 8, and 21 d) were tested in cages for ovarian development. Newly emerged, 4- and 8-d-old, and 21-d-old workers had medium-, large-, and small-sized ovaries, respectively, suggesting that of the worker ages tested only 4- and 8-d-old workers are likely to become egg layers in a queenless colony. Also, we compared ovarian development of newly emerged workers that were caged for 14 d and allowed to consume either pollen or royal jelly to that of another group of workers similarly caged but screened so that they could only obtain food via trophallaxis from young bees. Ovaries of newly emerged workers that received food from young bees were as well developed as those of newly emerged workers allowed to take pollen or royal jelly directly. Screened workers also had lower but still elevated vitellogenin levels compared with bees having direct access to food. These results indicate that nurse-age bees functioning as pollen-digesting units affect the ovarian development of other workers and to a lesser extent vitellogenesis via food exchange. We compared the influence of group sizes of 25, 125, and 600 bees per cage on ovarian development for 14 d. The two groups of 25 and 125 bees had similar mean ovary scores, and higher scores than a group of 600 bees. Our findings suggest that nurse-age bees could play an important role in mediating worker fertility via trophallaxis, possibly by differentiating worker dominance status, and generally only young workers become fertile when a queen is lost in a colony. Vitellogenin is a more sensitive parameter to measure bee fertility, and might be a useful tool to further explore ovary development and egg laying in worker social insects. We recommend measuring haemolymph vitellogenin titres and (or) oocyte length of workers in a group of 25 bees per cage, supplied with 50% royal jelly in honey as a standard method to assess honey bee worker fertility in future experiments. DOI
23. Westcott, LC; Winston, ML. (1999) Chemical acaricides in Apis mellifera (Hymenoptera : Apidae) colonies; do they cause nonlethal effects?Canadian Entomologist 131: 363-371 Chemical acaricides in Apis mellifera (Hymenoptera : Apidae) colonies; do they cause nonlethal effects?
Colonies of the honey bee, Apis mellifera Linnaeus, infested with the parasitic mites Acarcrpis woodi (Rennie) (Acari: Tarsonemidae) or Varroa jacobsoni Oudemans (Acari: Varroidae) require acaricidal treatment to control infestations that could affect colony growth and honey production. We investigated the effects of three acaricides, fluvalinate (formulated as Apistan(R)), formic acid, and menthol, on honey bee colony population growth, foraging activity, adult worker longevity, and honey production. Effects of in-hive treatments of Apistan(R) and formic acid were measured by examining colony weight gain, brood survival, sealed-brood area, emerged-bee weight, number of returning foragers, pollen-load weight, and worker longevity. These characteristics were not different between fluvalinate-treated colonies, formic-acid-treated colonies, and control colonies. Adult bee population, brood survival, number of returning foragers, and honey production did not vary among menthol-treated colonies, formic-acid-treated colonies, and control colonies. Sealed-brood area was lower in formic-acid-treated colonies than control colonies, but not different from menthol-treated colonies. Although not statistically significant, formic-acid-treated colonies experienced lower honey production than both menthol-treated and control colonies. Numbers of workers attending the queen in the retinue and queen behaviour patterns were not different after colonies were treated with formic acid.
22. Lin, HR; Winston, ML. (1998) The role of nutrition and temperature in the ovarian development of the worker honey bee (Apis mellifera).Canadian Entomologist 130: 883-891 The role of nutrition and temperature in the ovarian development of the worker honey bee (Apis mellifera)
Queenless, caged, newly emerged worker bees (Apis mellifera L.) were fed honey, 22 and 40% pollen in honey, and 22 and 40% royal jelly in honey for 14 days. Workers fed royal jelly, pollen, and honey had large, medium, and small ovaries; respectively. Royal jelly had higher nutritive value for workers' ovarian development than did pollen, possibly because royal jelly is predigested by nurse bees and easily used by adult and larval bees. These results suggest that nurse bees could mediate workers' ovarian development in colonies via trophallactic exchange of royal jelly. Six levels of royal jelly in honey, 0, 20, 40, 60, 80, and 100% (royal jelly without honey), were tested for their effects on workers' ovarian development and mortality for 10 days. High levels of royal jelly increased ovarian development, but also increased worker mortality. All caged bees treated with 100% royal jelly died within 3 days. When workers were incubated at 20, 27, and 34 degrees C for 10 days, only bees at 34 degrees C developed ovaries. These findings suggest that nurse bees functioning as units which digest pollen and produce royal jelly may feed some potentially egg-laying workers in a brood chamber with royal jelly when a queen is lost in a colony. Feeding workers a diet of 50% royal jelly in honey and incubating at 34 degrees C for 10 days is recommended for tests of ovarian development.
21. Pankiw, T; Huang, ZY; Winston, ML; Robinson, GE. (1998) Queen mandibular gland pheromone influences worker honey bee (Apis mellifera L.) foraging ontogeny and juvenile hormone titers.Journal of Insect Physiology 44: 685-692 Queen mandibular gland pheromone influences worker honey bee (Apis mellifera L.) foraging ontogeny and juvenile hormone titers
Apis mellifera; Queen mandibular gland pheromone; Division of labor; juvenile hormone; social insects
Synthetic queen mandibular gland pheromone (QMP) was applied to honey bee colonies to test two hypotheses: (i) QMP acts like a primer pheromone in the regulation of age-related division of labor, and (ii) this primer effect, if present, varies in three strains of workers that show genetically-based differences in their retinue attraction response to QMP !a pheromone releaser effect). Strains of workers that were high, or low in their response to QMP in a laboratory bioassay, as well as unselected 'wild-type' workers, were fostered in queenright colonies with or without supplemental QMP. Effects of QMP on foraging ontogeny and juvenile hormone III (JH) blood titers in worker honey bees were measured. Bees in QMP-supplemented colonies showed significant delays in foraging ontogeny, and foraging activity was reduced. They also had significantly lower JH titers, although the titer curves were somewhat atypical. There were no differences in foraging ontogeny or JH titers among the three strains. We conclude that (i) QMP can delay the ontogeny of foraging by some mechanism that suppresses JH production, (ii) this QMP primer response is independent of the retinue releaser response, and (iii) QMP can play an important role in regulating division of labour. (C) 1998 Elsevier Science Ltd. All rights reserved.
20. Pettis, JS; Westcott, LC; Winston, ML. (1998) Balling behaviour in the honey bee in response to exogenous queen mandibular gland pheromone.Journal of Apicultural Research 37: 125-131 Balling behaviour in the honey bee in response to exogenous queen mandibular gland pheromone
queen mandibular gland pheromone; honey bees; Apis mellifera; balling behaviour
Honey bee (Apis mellifera) colonies generally respond to the introduction of a foreign queen by aggressively surrounding or 'balling' the new queen. We explored the role of queen mandibular gland pheromone (QMP) in initiating balling behaviour. The addition of a synthetic blend of QMP to the abdomen of worker bees initiated balling behaviour of these workers when re-introduced into their own colony. There was a positive, dose-dependent relationship between the number of balls formed, time to ball formation and size of balls formed. When the QMP dose was below that normally found on a queen, 10(-3) queen equivalents, it resulted in significantly slower ball formation and smaller bail diameter. The acid components of the five-component QMP elicited balling behaviour while the aromatic components did not, but the full blend elicited the strongest response. Stinging behaviour was the most prevalent and persistent factor preceding the formation of balls. We concur with others who have proposed that a 'marking' pheromone is released when an aggressive worker flexes her abdomen, and that the release of this pheromone causes ball formation. There were no obvious changes in resident queen behaviour while balling of QMP-treated workers was occurring. We conclude that queen mandibular gland pheromone is a significant signal in foreign queen recognition and the initiation of balling behaviour.
19. Plettner, E; Slessor, KN; Winston, ML. (1998) Biosynthesis of mandibular acids in honey bees (Apis mellifera): De novo synthesis, route of fatty acid hydroxylation and caste selective beta-oxidation.Insect Biochem. Mol. Biol. 28: 31-42 Biosynthesis of mandibular acids in honey bees (Apis mellifera): De novo synthesis, route of fatty acid hydroxylation and caste selective beta-oxidation
hydroxylation; beta-oxidation; hydroxyacids; caste; honeybee; Apis mellifera
Fatty acids functionalized at the last (omega) and penultimate (omega-1) position, found in the mandibular glands of worker and queen honey bees (Apis mellifera L.), have important functions in the colony and are caste specific. Queens have predominantly 10-carbon omega-1-functionalized acids and workers have 10-carbon omega-functionalized acids. In previous work we have shown that the mandibular acids are synthesized from octadecanoic acid in three steps: (1) hydroxylation at the omega and omega-1 position; (2) beta-oxidation of the 18-carbon hydroxy acids to the 8 and 10-carbon length; and (3) oxidation of the omega- and omega-1-hydroxy groups to give diacids and 9-keto-2(E)-decenoic acid, respectively. The last two steps are caste selective, In this work, we studied the biosynthesis of mandibular acids from acetate, distinguished among two possible routes of hydroxylation and studied caste differences in hydroxy acid chain shortening. Workers glands biosynthesize mandibular acids from acetate and, therefore, do not depend on an external source of octadecanoic acid. Hydroxylation at the omega position proceeds with retention of label at the omega-1 position. Hydroxylation at the omega-1 position proceeds with retention of label at the omega position and does not involve a terminal double bond. Finally, hydroxy acid chain shortening differs in queens and workers in two respects: (1) the inhibition pattern in the presence of 2-fluorooctadecanoic acid; and (2) reversibility. Chain shortening is inhibited by 2-fluorooctadecanoic acid to a greater extent in workers than in queens, Furthermore, workers are able to elongate hydroxy acids to the next higher 2-carbon homologue and are able to reduce hydroxy-2(E)-decenoic acids to the corresponding hydroxydecanoic acids. These transformations were not detected in queens. (C) 1998 Elsevier Science Ltd. All rights reserved. DOI
18. Watmough, J; Winston, M; Slessor, K. (1998) Distinguishing the effects of dilution and restricted movement on the intra-nest transmission of honey-bee queen pheromones.Bull. Math. Biol. 60: 307-327 Distinguishing the effects of dilution and restricted movement on the intra-nest transmission of honey-bee queen pheromones
This paper develops a simple model for the movement of a non-volatile pheromone through a honey-bee hive. The model is specifically developed for a pheromone produced by the queen which is thought to regulate colony swarming. Although the model begins as a system of partial integro-differential equations, it is in the end reduced to a system of linear, first-order partial differential equations for the average pheromone level per worker, che pheromone level of the hive substrate, and the pheromone level of the queen. Analysis of this system shows that both colony size and hive area have independent effects on the average pheromone levels of the workers, hut that worker congestion can have an even stronger effect on the pheromone distribution. These results establish a relationship between colony size, hive area, worker crowding, and queen-pheromone transmission. (C) 1998 Society for Mathematical Biology. DOI
17.Winston, ML; Marceau, J; Higo, H; Cobey, S. (1998) Honey bee pheromones do not improve requeening success.American Bee Journal 138: 900-903 Honey bee pheromones do not improve requeening success
We examined the use of synthetic queen and worker honey bee pheromones to improve the rate of success requeening colonies. Most of the experiments used queen mandibular pheromone (QMP) added to colonies prior to or during new queen introduction, but we also tested worker Nasanov pheromone. No experiments demonstrated any increases in requeening success compared to control colonies, and in some experiments the use of QMP at higher dosages decreased the proportion of colonies requeened successfully. Thus, we do not recommend using pheromones during queen introduction.
16.Winston, ML; Slessor, KN. (1998) Honey bee primer pheromones and colony organization: gaps in our knowledge.Apidologie 29: 81-95 Honey bee primer pheromones and colony organization: gaps in our knowledge
Apis mellifera; primer pheromones; queen pheromones; colony integration
The purpose of this article is to discuss gaps in our knowledge concerning how honey bee primer pheromones mediate worker activities and colony functions. We first review the chemical structure and functions of queen mandibular pheromone (QMP), but then focus primarily on areas of potential future research interest. We discuss the mode of action that QMP may have on workers, address the issue of why QMP is a complex blend of five components, propose an evolutionary pathway for pheromone complexity in the genus Apis, discuss biochemical differences between worker and queen mandibular glands, review the evidence for additional queen pheromones besides QMP, examine how queen and brood pheromones interact to mediate colony biology, and discuss the relative importance of congestion and population size in pheromone transmission. Finally, we suggest some research areas that involve commercial applications of honey bee pheromones for beekeeping and crop pollination. (C) Intra/DIB/AGIB/Elsevier, Paris. DOI
15. Pettis, JS; Higo, HA; Pankiw, T; Winston, ML. (1997) Queen rearing suppression in the honey bee - evidence for a fecundity signal.Insectes Sociaux 44: 311-322 Queen rearing suppression in the honey bee - evidence for a fecundity signal
Apis mellifera; pheromones; queen rearing
Previous studies have shown that a pheromone produced in the honey bee (Apis mellifera L.) queen's mandibular glands suppresses the rearing of new queens. The present studies investigated the existence of an as-yet unidentified, brood-associated signal that acts in conjunction with the queen's mandibular pheromone to suppress queen rearing. When we manipulated the levels of synthetic queen mandibular gland pheromone (QMP) and young brood in queenless colonies, there was a 50% reduction in the number of queen cells reared compared to colonies receiving QMP alone. In a second experiment, colonies containing eggs and young larvae but no QMP reared on average only one queen cell after 24 h, while colonies containing older larvae reared four queen cells, suggesting that combs with younger brood were the source of the second signal. In a third experiment, we attempted to induce queen rearing in the presence of the queen by removing eggs and young larvae in colonies with healthy queens. Six of nine brood-manipulated colonies initiated queen cells, compared with only one of nine colonies receiving a sham manipulation. The results from this experiment suggest that a decline in the brood signal initiated queen supersedure in honey bee colonies. Results from all three experiments clearly demonstrate the existence of a "fecundity" signal that acts with QMP to suppress queen rearing.
14. Plettner, E; Otis, GW; Wimalaratne, PDC; Winston, ML; Slessor, KN; Pankiw, T; Punchihewa, PWK. (1997) Species- and caste-determined mandibular gland signals in honeybees (Apis).J. Chem. Ecol. 23: 363-377 Species- and caste-determined mandibular gland signals in honeybees (Apis)
honeybee; mandibular gland; chemical signature; pheromone; queen; worker; Apis
Queens and workers of five honeybee species (Apis mellifera, A. cerana, A. dorsata, A. florea, and A. andreniformis) were analyzed for their mandibular gland components. In A. mellifera, the queen mandibular pheromone consists of 9-hydroxy- and 9-keto-2(E)-decenoic acids (8-HDA and ODA), methyl p-hydroxybenzoate (HOB), and 4-hydroxy-3-methoxyphenylethanol (HVA), and is responsible for retinue attraction, among other functions. In retinue bioassays with workers of A. cerana (whose queens lack HVA), ODA, 9-HDA, and HOB were sufficient to elicit maximal retinue behavior. This suggests that the known queen mandibular pheromone components detected in mandibular glands of A. cerana queens constitute the functional queen mandibular pheromone in this species. Both castes of A. mellifera produce 10- and 8-carbon acids that are functionalized at the last position in the chain, and these are the predominant compounds found in worker mandibular glands. Workers of the other species also had these compounds, along with 9-HDA and ODA that are normally not present in A. mellifera worker glands. Queens and workers of each species had a unique combination of mandibular compounds. The aromatic compounds were characteristic of queens from the cavity-nesting species, A. mellifera (HOB and HVA) and A. cerana (HOB). These two species also had more pronounced differences in the mandibular blends of queens and workers than the open-nesting species, A. dorsata, A. florea, and A. andreniformis. Our results indicate that the more derived cavity-nesting species of Apis have evolved greater caste-specific differences between queens and workers and a higher number of queen pheromone components, compared to the open-nesting species. DOI
13. Robinson, GE; Fahrbach, SE; Winston, ML. (1997) Insect societies and the molecular biology of social behavior.Bioessays 19: 1099-1108 Insect societies and the molecular biology of social behavior
This article outlines the rationale for a molecular genetic study of social behavior, and explains why social insects are good models. Summaries of research on brain and behavior in two species, honey bees and fire ants, are presented to illustrate the richness of the behavioral phenomena that can be addressed with social insects and to show how they are beginning to be used to study genes that influence social behavior. We conclude by considering the problems and potential of this emerging field.
12. Melathopoulos, AP; Winston, ML; Pettis, JS; Pankiw, T. (1996) Effect of queen mandibular pheromone on initiation and maintenance of queen cells in the honey bee (Apis mellifera L).Canadian Entomologist 128: 263-272 Effect of queen mandibular pheromone on initiation and maintenance of queen cells in the honey bee (Apis mellifera L)
Adding queen mandibular pheromone into honey bee colonies earlier than 24 h after queen loss resulted in an inhibition of queen-rearing, but not when added after 4 days. The number of queen cells initiated in each treatment decreased with the addition of the pheromone, although there were no effects on the number of queen cells tom down following pheromone treatment. The effect of adding the pheromone to queenless colonies given newly hatched female larvae under different regimens of queen cell provisioning and cell structure also was investigated, Only colonies in which larvae were presented in unmodified worker comb exhibited significantly lower rates of queen-rearing. Results indicate that queen mandibular pheromone inhibits the initiation of queen-rearing but not the maintenance of established cells.
11. Pankiw, T; Winston, ML; Plettner, E; Slessor, KN; Pettis, JS; Taylor, OR. (1996) Mandibular gland components of European and Africanized honey bee queens (Apis mellifera L).Journal of Chemical Ecology 22: 605-615 Mandibular gland components of European and Africanized honey bee queens (Apis mellifera L)
Apis mellifera; honey bee; queen mandibular gland pheromone; Africanized honey bee
The composition of the five-component honey bee queen mandibular gland pheromone (QMP) of mated European honey bee queens was compared to those of virgin and drone-laying (i.e., laying only haploid unfertilized eggs that develop into males), European queens and Africanized mated queens. QMP of mated European queens showed significantly greater quantities of individual components than all queen types compared, except for a significantly greater quantity of 9-hydroxy-(E)-2-decenoic acid (9-HDA) found in Africanized queens. Glands of European drone-laying queens contained quantities intermediate between virgin and mated queens, reflecting their intermediate reproductive state and age. QMP ontogeny shifts from a high proportion of 9-keto-(E)-2-decenoic acid (ODA) in young unmated queens to roughly equal proportions of ODA and 9-HDA in mated queens. A biosynthetic shift occurs after mating that results in a greater proportion of 9-HDA, methyl p-hydroxybenzoate (HOB), and 4-hydroxy-3-methoxyphenylethanol (HVA) production, accompanied by a decreased proportion of ODA. Africanized QMP proportions of ODA and 9-HDA were significantly different from European queens. A quantitative definition of a ''queen equivalent'' of QMP is proposed for the various queen types, and a standard queen equivalent for mated European honeybee queen mandibular gland pheromone is adopted as 200 mu g ODA, 80 mu g 9-HDA, 20 mu g HOB, and 2 mu g HVA.
10. Plettner, E; Slessor, KN; Winston, ML; Oliver, JE. (1996) Caste-selective pheromone biosynthesis in honeybees.Science 271: 1851-1853 Caste-selective pheromone biosynthesis in honeybees
Queen and worker honeybees (Apis mellifera L.) produce a caste-related blend of functionalized 8- and 10-carbon fatty acids in their mandibular glands. The biological functions of these compounds match the queen's reproductive and the worker's nonreproductive roles in the colony. Studies with deuterated substrates revealed that the biosynthesis of these acids begins with stearic acid, which is hydroxylated at the 17th or 18th position. The 18-carbon hydroxy acid chains are shortened, and the resulting 10-carbon hydroxy acids are oxidized in a caste-selective manner, thereby determining many of the functional differences between queens and workers.
8. ECKERT, CD; WINSTON, ML; YDENBERG, RC. (1994) THE RELATIONSHIP BETWEEN POPULATION-SIZE, AMOUNT OF BROOD, AND INDIVIDUAL FORAGING BEHAVIOR IN THE HONEY-BEE, APIS-MELLIFERA L.Oecologia 97: 248-255 THE RELATIONSHIP BETWEEN POPULATION-SIZE, AMOUNT OF BROOD, AND INDIVIDUAL FORAGING BEHAVIOR IN THE HONEY-BEE, APIS-MELLIFERA L
HONEY BEE; FORAGING BEHAVIOR; COLONY STATE
This study experimentally examines the relationship between colony state and the behaviour of individual pollen and nectar foragers in the honey bee, Apis mellifera L. In the first experiment we test the prediction that individual pollen foragers from colonies with higher brood quantities should exhibit a greater work effort for pollen resources than individual pollen foragers from colonies with low brood quantities. Eight colonies were assigned into two treatment groups; HIGH brood colonies were manipulated to contain 9600+/-480 cm2 brood area; LOW brood colonies were manipulated to contain 1600+/-80 cm2 brood area. We measured colony brood levels over the course of the experiment and collected individual pollen loads from returning pollen foragers. We found that, while colonies remained significantly different in brood levels, individual pollen foragers from HIGH brood colonies collected larger loads than individuals from LOW brood colonies. In the second experiment we investigated the influence of colony size on the behaviour of individual nectar foragers. We assigned eight colonies to two treatment groups; LARGE colonies were manipulated to contain 35000+/-1700 adult workers with 3500+/-175 cm2 brood area, and SMALL colonies were manipulated to contain 10000+/-500 adult workers with 1000+/-50 cm2 brood area. We observed foraging trips of individually marked workers and found that individuals from LARGE colonies made longer foraging trips than those from SMALL colonies (LARGE: 1666.7+/-126.4 seconds, SMALL: 1210.8+/-157.6 seconds), and collected larger nectar loads (LARGE: 19.2+/-1.0 mul, SMALL: 14.6+/-0.8 mul). These results indicate that individual nectar foragers from LARGE colonies tend to work harder than individuals from SMALL colonies. Both experiments indicate that the values of nectar and pollen resources to a colony change depend on colony state, and that individual foragers modify their behaviour accordingly. DOI PubMed
7. NAUMANN, K; WINSTON, ML; SLESSOR, KN; SMIRLE, MJ. (1994) SYNTHETIC HONEY-BEE (HYMENOPTERA, APIDAE) QUEEN MANDIBULAR GLAND PHEROMONE APPLICATIONS AFFECT PEAR AND SWEET CHERRY POLLINATION.J. Econ. Entomol. 87: 1595-1599 SYNTHETIC HONEY-BEE (HYMENOPTERA, APIDAE) QUEEN MANDIBULAR GLAND PHEROMONE APPLICATIONS AFFECT PEAR AND SWEET CHERRY POLLINATION
APIS MELLIFERA; PHEROMONE; POLLINATION
Synthetic honey bee queen mandibular pheromone, Fruit Boost, was applied to 'Anjou' pear, Pyrus communus I,., and 'Bing'-type sweet cherry trees, Prunus avium L., in bloom using air blast sprayers. In pear, the application of 1,000 queen equivalents of active ingredients per hectare resulted in a 7% increase in fruit size and a $400 per hectare net increase in income, although there were no significant increases in bee visits or fruit set in treated Versus untreated plots. Two consecutive pheromone applications were not significantly different than a single application. In cherry, sprays of 100 or 500 queen equivalents per hectare did not affect bee visits, fruit set, or fruit size. Our results show that applications of mandibular pheromone can enhance pollination in pear but not in sweet cherry. DOI
6. SCHMIDHEMPEL, P; WINSTON, ML; YDENBERG, RC. (1993) INVITATION PAPER (ALEXANDER,C.P. FUND) - FORAGING OF INDIVIDUAL WORKERS IN RELATION TO COLONY STATE IN THE SOCIAL HYMENOPTERA.Can. Entomol. 125: 129-160 INVITATION PAPER (ALEXANDER,C.P. FUND) - FORAGING OF INDIVIDUAL WORKERS IN RELATION TO COLONY STATE IN THE SOCIAL HYMENOPTERA
Workers of social insects are members of colonies that survive and reproduce together. Therefore, the behavioral activities of individual workers should be integrated with colony state. We here summarize and discuss the relationship between colony state and foraging behavior of individual workers under the provisional assumption that the colony is a unit. We argue that colony state can be described by a number of variables that should relate to fitness components in order to be meaningful. Among the possible candidates, colony population size seems to have an overriding importance in many respects, as shown by its relation to fitness components such as survival probability and reproductive performance. Other important variables include colony demography, i.e. caste or size distributions, nutritional status, or queen number. Each of these variables has been shown to affect fitness components; however, the evidence is rather scanty. We also discuss the evidence that variation in colony state variables relates to variation in individual worker behavior. Nutritional status (i.e. low or high levels of food stores) and colony size have been shown repeatedly to affect individual behavior. However, most of the evidence comes from the honey bee. Some studies suggest that behavioral responses are hierarchically structured. More work needs to be done to investigate the actual mechanisms of integration of individual behavior with colony state. Some knowledge has accumulated about the processes that govern recruitment to food sources. We conclude this review by discussing some concepts and problems for further research. These include the concept of a preferred colony state to which the colony should return after disturbance through the behavioral activities of the workers. Further theoretical elaboration and empirical investigations may help to elucidate whether this concept is useful and necessary. A largely neglected issue concerns the number versus effort problem, i.e. whether individuals should work harder or more workers should be allocated to a task that is in demand. We propose a simple scenario that suggests testable predictions. Finally, we discuss how colony state, individual work load, and the dependence of worker mortality rate on activity level may interact to generate different short-term foraging strategies that workers should adopt. DOI
5. HIGO, HA; COLLEY, SJ; WINSTON, ML; SLESSOR, KN. (1992) EFFECTS OF HONEY-BEE (APIS-MELLIFERA L) QUEEN MANDIBULAR GLAND PHEROMONE ON FORAGING AND BROOD REARING.Can. Entomol. 124: 409-418 EFFECTS OF HONEY-BEE (APIS-MELLIFERA L) QUEEN MANDIBULAR GLAND PHEROMONE ON FORAGING AND BROOD REARING
We investigated the effects of synthetic honey bee (Apis mellifera L.) queen mandibular gland pheromone on colony foraging and brood rearing. Colonies newly established in the spring showed a significant, dose-dependent increase in the number of foragers gathering pollen, and individual pollen foragers returned to the nest with larger pollen loads. These two effects combined resulted in a doubling of the amount of pollen brought into colonies by foraging bees. Brood rearing also increased, but not significantly. In contrast, large, established colonies showed no effects at their summer population peak. We conclude that queen mandibular pheromone can significantly affect foraging, but its effects depend on colony conditions and environmental factors. DOI
4. NAUMANN, K; WINSTON, ML; SLESSOR, KN; PRESTWICH, GD; LATLI, B. (1992) INTRA-NEST TRANSMISSION OF AROMATIC HONEY-BEE QUEEN MANDIBULAR GLAND PHEROMONE COMPONENTS - MOVEMENT AS A UNIT.Can. Entomol. 124: 917-934 INTRA-NEST TRANSMISSION OF AROMATIC HONEY-BEE QUEEN MANDIBULAR GLAND PHEROMONE COMPONENTS - MOVEMENT AS A UNIT
The intra-nest transmission of two aromatic components of honey bee queen mandibular gland pheromone, 4-hydroxy-3-hydroxyphenylethanol (HVA) and methyl p-hydroxybenzoate (HOB), is quantitatively described. After being secreted onto the body surface of the queen, the greatest quantities of HVA and HOB are removed by workers in the queen's retinue, especially those contacting the queen with their mouthparts. Other workers acquire pheromone components via direct contact with retinue bees or with other workers that have already acquired queen pheromone. HVA and HOB can also reach workers through queen or worker ''footprints,'' although die relatively little material deposited onto the comb wax becomes less available with time, presumably because of diffusion into the wax. Pheromone material is removed from circulation by being internalized into workers, the queen, and the wax. Rates of HVA and HOB transfer between different entities within the nest are described in terms of pseudo first-order rate constants. The intra-nest transfer of these two components, both qualitatively and quantitatively, is similar to that described earlier for the most abundant queen mandibular gland pheromone component, 9-keto-2-(E)-decenoic acid (9-ODA; Naumann et al. 1991). Thus, the queen mandibular gland pheromone complex is transferred through the nest as a unit rather than as individual components moving at different rates. DOI
1. WILLIS, LG; WINSTON, ML; SLESSOR, KN. (1990) QUEEN HONEY-BEE MANDIBULAR PHEROMONE DOES NOT AFFECT WORKER OVARY DEVELOPMENT.Can. Entomol. 122: 1093-1099 QUEEN HONEY-BEE MANDIBULAR PHEROMONE DOES NOT AFFECT WORKER OVARY DEVELOPMENT
This study examined the dose-dependent effects of synthetic honey bee queen mandibular pheromone on the inhibition of worker ovary development. The range of doses examined was from 10-3 to 10 queen equivalents (Qeq) per day for days; 1 Qeq was the amount of pheromone in an average pair of queen mandibular glands. Ovary class and ovariole number scores were used as estimates of worker ovary development. Queen mandibular pheromone did not inhibit ovary development in workers at any dose. DOI
