Meeting Abstract
Animals modify their behavior in response to ecological factors, and one pathway by which behavioral responses may be regulated is through glucocorticoids (GCs). GCs are released in response to adverse situations, and as such often referred to as ‘stress hormones’. However, GCs play roles in many aspects of animal biology, and studies involving artificial increases in GCs have found effects on diverse behaviors in different species. In North American red squirrels (Tamiasciurus hudsonicus), population density, which is perceived by squirrels through neighbor rattles, is an important ecological factor. Perceived population density has been found to increase GCs in pregnant females and affect behavior in male and female squirrels. Other ecological factors that may affect squirrel behavior include ambient temperature and reproductive state. Here, we studied the effects of GC supplements, reproductive state, temperature, and neighbor rattles on behavior in a population of wild squirrels in the Yukon, Canada. We supplemented pregnant squirrels with peanut butter containing 12mg of GCs (high dose) or not containing GCs (control dose) daily from mid-pregnancy to five days postpartum. Other breeding females were supplemented during lactation with high and control doses from days 5-15 post-partum. Non-breeding squirrels were also included, with males and females fed control or high doses for 21 days after the end of the breeding season. Squirrels were fitted with radio-collars and behavioral data were collected in seven minute focal sessions. Behavioral data were analyzed to test for effects of GC treatment, sex, reproductive status, temperature, and rates of neighbor rattles on squirrel behavior. Results from these analyses will be discussed.
