Meeting Abstract
P3.76 Tuesday, Jan. 6 The relationship between stress hormones and life history strategies during the non-breeding season in three species of cardueline finches KNUTIE, S.A.*; PEREYRA, M.E.; University of Tulsa; University of Tulsa sarah-knutie@utulsa.edu
Birds residing in temperate areas during the winter are often confronted with unpredictable weather conditions, reduced resource availability, and shorter days leaving less time to forage. The physiological and behavioral changes necessary to cope with these conditions are mediated in part by glucocorticoids, which enable survival and help increase fitness. Elevated corticosterone during periods of food deprivation or adverse weather events are often associated with increases in foraging and locomotor activity, which may translate into local irruptive movements in some species. Several species of cardueline finches can be found wintering in the south-central Great Plains, a region characterized by highly unpredictable and somewhat extreme conditions. Two of these species, the pine siskin (Carduelis pinus) and purple finch (Carpodacus purpureus) are nomadic, rarely returning to the same wintering areas in successive years. They often partake in sporadic irruptive migrations, which may be related to exogenous cues such as decreased resource availability and adverse weather events. Other species of cardueline finches such as the American goldfinch (Carduelis tristis) are only semi-nomadic during the winter. We investigated the relationship between size, body condition and corticosterone levels (baseline and acute response to stress) in relation to season, annual cycle, and adverse weather events in purple finches, pine siskins, and American goldfinches. In December 2007, Oklahoma experienced a severe ice storm, which destroyed or damaged large numbers of trees. Blood samples were collected the days before, during, and following the storm. Differences in stress physiology between the three species of cardueline finches during the non-breeding season will be discussed.
