Effects of Scale and Gender on Winter Habitat Selection by American Mink

Abstract

Mammalian carnivores have adapted to successfully occupy a wide range of environments spanning tropical to polar ecosystems. Some species, however, have evolved in ways that constrain their ability to thrive in extreme environmental conditions. For example many members of the Family Mustelidae are vulnerable to extreme temperatures resulting from their tubular body shape. The American mink (Neovison vison) likely faces these temperature constraints, being a smaller-bodied mustelid that ranges over a large portion of North America. Mink are largely understudied in its native range with knowledge being particularly sparse with respect to winter ecology. During 2011–2012 we conducted winter telemetry on seven adult mink and used resource selection function models to assess habitat selection patterns while considering spatial extent and gender. We found that at a larger extent, the animals' use of habitat was strongly linked to riparian features, whereas this effect was less noticeable at a finer scale. The larger males selected more lakeshore habitat, whereas the smaller females generally were near smaller streams with both selecting for beaver modified habitat. While we recognize the limited sample size in our study, we speculate that this spatial separation could be linked to higher energetic costs for females to forage aquatically in winter because of their smaller body size. This may make females more sensitive to competition from other forest carnivores (e.g. American marten) as well as impacts from resource development activities.