Effects of Age, Sex and Weight on Social Rank in Penned White-tailed Deer

Abstract

Relationships of dominance to age, sex and weight were examined in a herd of penned white-tailed deer (Odocoileus virginianus borealis) for 3 years near Guelph, Ontario. Hierarchies were constructed for each month using a method which minimized dominance triangles. Adult males ranked significantly higher (P <0.05) than adult females in all but 3 months, higher than yearling males in six of 15 months, and higher than other classes in all months with sufficient data for comparisons. Adult females dominated (P<0.05) yearling males in seven of 15 months, primarily in summer and autumn. Adult females ranked significantly above (P<0.05) yearling females until after the peak in rut, but did not rank significantly higher thereafter. Fawn females were uniformly subordinate to adult does, but fawn males began in their first rut to dominate adult and yearling does. Mean rank of yearling males was always higher than yearling females, but statistical comparisons were impossible. Yearling females were usually ranked above fawns although no statistical differences were evident. Difference in mean ranks between male and female fawns was never statistically significant, but mean rank of males was always higher. Partial correlations showed that virtually all variation in rank accounted for by coefficients of multiple determination was explained by weight in males and age in females. Importance of weight in males reflected strength and endurance necessary to win severe fights. Outcome of contests between does depended on conditioning, persistence and experience gained with age.