Cortisol levels, dominance rank and mating opportunities in Père David's deer stags

摘要

We conducted an experiment in the Beijing Milu Park to study the social behavior of male Père David's deer, Elaphurus davidianus, and explored the relationship between social position and serum cortisol level. We classified the stags into a dominant group which included the “harem master” and “challenger”, and a subordinate group which included “bachelor” and “post-rut master”, then monitored behavior of these stags whilst analyzing serum cortisol concentrations in the observed stags. We found that (1) the dominant stags displayed rut behaviors more frequently than the subordinate stags, (2) there was no significant difference in aggressive behaviors between the two groups, and (3) although it seemed that serum cortisol concentrations of one harem master was higher than that of one bachelor, we did not find the significant difference of cortisol levels between the two groups. We conclude that social rank affects social behaviors of Père David's deer stag during rut. Père David's deer stag maintain reproductive competence in the face of increased physical and psychological stress during rut [Acta Zoologica Sinica 49(5): 566 - 570, 2003].