Under a Neighbor's Influence: social information impacts stress physiology and behavior in a songbird

Social information is recognized to have potent impacts on reproductive behavior and physiology, however, much less is known regarding the impacts of social information in the context of migration.
We present past and present work concerning the influence of social information on behavior and physiology of a facultative migrant, the red crossbill (Loxia curvirostra). Evidence suggests that this species is quite responsive to social information about food – with the ability to learn from neighbors about novel foraging techniques, to adjust fat deposition in response to declining food of neighbors and to adjust hypothalamic-pituitary-adrenal activity in both plasma hormone (i.e., corticosterone) and brain receptor (i.e., mineralocorticoid and glucocorticoid receptor) levels when neighbors are food limited. We discuss these results in the context of facultative migration and adaptation to unpredictable resources.