An observational analysis of Canada Jay (Perisoreus canadensis) foraging and caching ecology in Denali National Park and Preserve, Alaska, USA

Abstract

Arctic and subarctic wildlife are among the most vulnerable species to climate change. Canada Jays (Perisoreus canadensis (Linnaeus, 1776)) are generalist residents of northern boreal forests and scatter-hoard food to insulate against food scarcity during winter. Unlike most scatter-hoarders, however, Canada Jays primarily cache perishable food, rendering their caches more susceptible to climate change induced degradation and loss. Here we use a mostly noninvasive approach to document Canada Jay foraging ecology among a population in interior Alaska, USA, including the types of food acquired, foraging and caching rates, and cache longevity and loss. We also tested for associations between foraging and caching rates with reproductive metrics to assess possible relationships among food and productivity. We found that Canada Jays have a varied diet that changed seasonally, and responded to a record-setting warm spring by directing foraging efforts away from cache recovery and towards the emergence of fresh food. We did not find evidence for relationships between foraging and caching rate with reproductive output, possibly owing to small sample sizes. We found that caches were recovered quickly (<4 weeks) and frequently lost to conspecific and heterospecific competitors. Our study suggests that Canada Jays may be better poised to respond to changes in cache integrity and food availability than has been previously recognized.