Corticosterone in feathers is a long-term, integrated measure of avian stress physiology

1. Stress has pervasive consequences for the well-being of animals. Currently, understanding how individuals cope with stressors is typically accomplished via short-term quantification of blood glucocorticoids released after activation of the hypothalamic–pituitary–adrenal (HPA) axis. 2. We investigated whether the amount of corticosterone (CORT) deposited in growing feathers provides a long-term, integrated measure of HPA activity […]

Female polar bears, Ursus maritimus, on the Barents Sea drift ice: walking the treadmill

For animals in dynamic habitats, the contribution of passive (i.e. by wind or current) and active (movements by the animals themselves) displacement determines whether their space use reflects physical or adaptive behavioural processes. Polar bears in the Barents Sea undertake extensive annual migrations in a habitat that is highly dynamic because of continuous sea ice […]

Effect of environmental stress and immobilization on stress physiological variables in farmed mink

The effect of cage size and nest box environment on plasma cortisol, number of eosinophil leucocytes, and on frequency of leucocyte groups was measured on 132 farmed mink. The experiment included three cage sizes (0.10 m2, 0.27 m2, and 1.1 m2) and cages with and without nest boxes. Furthermore, the effect of daily immobilization a […]

Measuring Fecal Glucocorticoid Metabolites in Mammals and Birds: The Importance of Validation

In recent years, the noninvasive monitoring of steroid hormone metabolites in feces of mammals and droppings of birds has become an increasingly popular technique. It offers several advantages and has been applied to a variety of species under various settings. However, using this technique to reliably assess an animal’s adrenocortical activity is not that simple […]

Seasonal variation in the length of the daily activity period in buffy-headed marmosets (Callithrix flaviceps): An important consideration for the analysis of foraging strategies in observational field studies of primates

Activity budgets are widely used in primate behavioral studies for the analysis of ecological strategies. In some cases, there is considerable seasonal variation in the length of the daily activity period. Here, activity budgets from two field studies of Callithrix flaviceps were compiled first by the traditional approach (proportion of scan sample records) and then […]

Effects of seasonal changes in dietary energy on body weight of captive Japanese macaques (Macaca fuscata)

Food availability varies seasonally for wild animals, and body weight fluctuates accordingly in the wild. In contrast, controlling availability of diet under captive condition is difficult from keepers’ standpoint, and monotonous diet often causes health problems in captive animals. We evaluated the effects of a seasonally controlled diet on body weight of captive Japanese macaques […]