SOCIAL-DOMINANCE IN ADULT FEMALE MOUNTAIN GOATS

The social behaviour of adult female mountain goats, Oreamnos american us, was studied for 2 years in an unhunted population in west-central Alberta, Canada. Compared with other female ungulates, mountain goat f emales interacted aggressively much more frequently and their dominanc e ranks were less stable in time and less age-related. Goats were orga nized in a non-linear but non-random dominance hierarchy, with many re versals in rank. The best morphological predictor of dominance rank wa s horn length one year and body mass in the following year. Age was a weaker predictor of dominance status than what has been reported for o ther female ungulates. The ranks of individual goats changed between y ears and dominance rank one year was not a good predictor of rank the following year. These results suggest that linearity may only be possi ble when a contested resource can be defended. Dominant female goats d id not forage more efficiently than subordinate goats, and dominant st atus did not affect the amount of time devoted to alert behaviour.