Seasonal Ranges of Dall's Sheep, Mackenzie Mountains, Northwest Territories

Abstract

The seasonal distribution of marked Dall's sheep in the Mackenzie Mountains was studied during 1968 through 1974 as part of a broader Canadian Wildlife Service project that included research into population dynamics and hunter kill statistics. Dyes were used to mark 247 sheep, and 118 were marked with collars, ear tags, and ear streamers. Aerial observations of sheep and their winter tracks were the basis for maps of seasonal ranges. Summer ranges were a 30-90% expansion of winter ranges within mountain blocks that were bounded by forests and stream valleys. Within the study areas, these mountain blocks served as year-long habitat for most members of family groups of ewes and juveniles. Winter ranges were characterized by shallow, lightly crusted or uncrusted granular snow that did not impede travel or seriously constrict feeding areas. A few sheep wintered in forests near river banks. During summers, mineral licks dictated the shape of family group ranges, as well as the length and patterns of their daily and seasonal movements.

Key words: Dall's sheep (Ovis dalli), seasonal ranges, mackenzie Mountains, marking, dispersal, mineral lick