The Social structure and behavior of an Alaskan wolf population

Haber, Gordon

(Adapted from author's abstract.) This 1968 master's thesis focuses on a two-year study conducted in 1966 and 1967 on a population of free-ranging wolves in a 1500-square-mile area of Mount McKinley National Park. The author investigated the social structure and behavior of two wolf packs that ranged entirely within the study area and also collected some data for three packs on the periphery of the study area. One pack of 10 wolves utilized a home range of about 420 square miles. The size, number of families, and extent of home range of this pack were the same in 1967 as in 1940, suggesting that the social structure of the pack remained relatively stable over a 27-year period. A second pack of about 28 wolves utilized a home range of approximately 660 square miles. No interpack interactions were observed, but there appeared to be a 'no-man's-land' between adjacent territories of the two major packs. In 1967 an estimated 8400 caribou, 250-350 moose, and 2000-3000 Dall sheep used the study area. The production and/or survival of young appeared to be high in moose, but low in caribou and sheep. Each major prey species was utilized by wolves in proportion to its relative availability. Moose were the most abundant prey animals within the home range of the small pack and comprised most of this pack's diet during the entire year. During the summer caribou were the most abundant prey within the home range of the larger pack and comprised most of this pack's summer diet. Wolves did not follow migrating caribou out of the study area. Rather, home ranges remained relatively stable and moose and sheep provided most of the winter food. Calves supported the greatest relative predation load in both moose and caribou.