Marine subsidies mediate patterns in avian island biogeography


Back to previous page
Authors: Obrist, DS; Hanly, PJ; Kennedy, JC; Fitzpatrick, OT; Wickham, SB; Ernst, CM; Nijland, W; Reshitnyk, LY; Darimont, CT; Starzomski, BM; Reynolds, JD
Year: 2020
Journal: Proc. R. Soc. B-Biol. Sci. 287   Article Link (DOI)
Title: Marine subsidies mediate patterns in avian island biogeography
Abstract: The classical theory of island biogeography, which predicts species richness using island area and isolation, has been expanded to include contributions from marine subsidies, i.e. subsidized island biogeography (SIB) theory. We tested the effects of marine subsidies on species diversity and population density on productive temperate islands, evaluating SIB predictions previously untested at comparable scales and subsidy levels. We found that the diversity of terrestrial breeding bird communities on 91 small islands (approx. 0.0001-3 km(2)) along the Central Coast of British Columbia, Canada were correlated most strongly with island area, but also with marine subsidies. Species richness increased and population density decreased with island area, but isolation had no measurable influence. Species richness was negatively correlated with marine subsidy, measured as forest-edge soil delta N-15. Density, however, was higher on islands with higher marine subsidy, and a negative interaction between area and subsidy indicates that this effect is stronger on smaller islands, offering some support for SIB. Our study emphasizes how subsidies from the sea can shape diversity patterns on islands and can even exceed the importance of isolation in determining species richness and densities of terrestrial biota.
Back to previous page
 

Please send suggestions for improving this publication database to sass-support@sfu.ca.
Departmental members may update their publication list.