Synergistic effects of spring temperatures and land cover on nest survival of urban birds

Abstract

ABSTRACT Climate change has the potential to influence avian population dynamics through nest-fate sensitivity to temperatures during the breeding season. Nest fate also varies across spatially heterogeneous habitat, and changing land uses may independently introduce stressors on reproductive outcome. Identifying the individual and synergistic effects of climate change and land-use change is necessary for understanding the impact of global change on native species. We studied the nest fate of 3 sympatric species breeding in urban habitat in an arid region of the western United States. We monitored nests (n = 371) of American Robin (Turdus migratorius), Mourning Dove (Zenaida macroura), and Black-headed Grosbeak (Pheucticus melanocephalus) over 4 yr on an urban-to-rural gradient and analyzed nest fate in relation to temperatures at the time of egg laying and after eggs hatched. Habitat measurements included nest height and the amounts of canopy cover and impervious surfaces at 3 spatial scales of 20-m, 100...