Wolf-avoidance strategies of moose

Two possible anti-predator strategies of prey were suggested by the distribution of moose at Isle Royale, a 544 km² island with numerous offshore islets. Aerial surveys in winter indicated that moose density on small islets (<1.5 km²) averaged 415% greater than on the main island, with about 11% of the calf population existing on the small islets which comprise less than 2% of the total land area. On small islets and shorelines, protection from wolves (in the form of escape terrain) is provided by nearby water in summer and coniferous cover in winter. Calves on islands appear to have a higher survival rate. In summer, cow moose with calves were seen more commonly in camps with human activity (and no wolves) than away from camps, suggesting that people provided a refuge from wolf predation for this unhunted moose population. These subtle patterns of habitat selection by moose are attributed to the intensive natural selection pressure of wolf predation.