Measuring corticosterone in feathers using an acetonitrile/hexane extraction and enzyme immunoassay: feather corticosterone levels of food-supplemented Atlantic Puffin chicks

Glucocorticoid levels measured in the blood of animals reflect hypothalamic-pituitary-adrenal (HPA) activity in response to predictable and unpredictable changes. In birds, circulating corticosterone is incorporated into growing feathers and provides an integrated measure of HPA activity over the period of feather growth. Measuring corticosterone in feathers can provide insight into the physiological state of birds during times when they are...