Patterns of Fecal Hormones in a Fenced Population of White-Tailed Deer

Analysis of voided feces has become a popular method of monitoring physiological parameters of many wildlife species. During the breeding seasons of 2006-2007 and 2007-2008, we collected fecal samples to determine concentrations of fecal glucocorticoid (FG) and fecal testosterone (FT) metabolites in a fenced population of white-tailed deer (Odocoileus virginianus). The purpose of the study was to determine how concentrations of FG and FT metabolites fluctuated throughout the breeding season, whether there was a difference between males and females, and whether there was a relationship between the two hormones. FG and FT metabolites of males peaked during the rut, while female glucocorticoid levels remained relatively stable throughout the breeding season. We also observed a significant positive correlation between FG and FT metabolites. During the pre-rut and rut, males that exhibit high testosterone also had elevated glucocorticoid metabolite concentrations, but in the post-rut there was no relationship between FT and FG concentrations. We hypothesize that the effect of testosterone on glucocorticoid secretion is partially a result of testosterone-induced behavior, and not strictly a physiological link between the two hormones. (C) 2012 The Wildlife Society.