Meeting Abstract
Spatial variation in resources presents a unique challenge to migrant birds. Red crossbills, Loxia curvirostra, are a nomadic finch specializing on conifer seeds that show high degrees of spatial variation but low temporal variation – generally becoming available for use in the summer. We have previously shown that crossbills prepare for spring movements by depositing fat, presumably to mitigate the risks inherent to finding unpredictably distributed resources. Here we describe how corticosterone relates to these seasonal changes and further test how manipulation of foraging effort influences behavior and physiology during the spring migratory period. We predict that increasing foraging effort will intensify or prolong migratory behavior and physiology of nomadic migrants.
