Stable isotopic niche predicts fitness of prey in a wolf–deer system

摘要: Interindividual variation in niche presents a potentially central object on which natural selection can act. This may have important evolutionary implications because habitat use governs suite of selective forces encountered by foragers. In free-living native black-tailed deer, Odocoileus hemionus , population from coastal British Columbia, we used stable isotope analysis to identify individual foraging and investigated its relationship fitness. Using an intragenerational comparison surviving nonsurviving O. over 2 years predation wolves, Canis lupus, detected resource-specific Individuals with isotopic signatures that suggested they foraged primarily cedar ( Thuja plicata )-dominated low-elevation hemlock Tsuga heterophylla )dominated forest stands were more likely be killed C. lupus . High-quality forage T. stands, as indexed protein content, involved maintaining this phenotype. Moreover, nonsurvivors diverged than survivors median signatures, suggesting against specialization. Stable provides novel opportunity integrate ecological landscapes order underlying mechanisms provide insight into the maintenance variability. © 2007 The Linnean Society London, Biological Journal 2007, 90 125‐137.