Diet selection in Arctic lemmings (Lemmus sibiricus and Dicrostonyx groenlandicus): demography, home range, and habitat use

In this study we explore the relationships between demography, patterns of habitat use, and the diets selected by Lemmus and Dicrostonyx at Igloolik Island, N.W.T. The demography of both species at Igloolik is similar to that recorded at other localities, but maximal densities vary between sites and may be related to the abundance of suitable forage. Home range characteristics and patterns of habitat use in each lemming species are related to the spatial and temporal distribution of preferred foods: in summer, Lemmus uses low-lying wet meadow habitats dominated by graminoids and mosses, whereas Dicrostonyx uses mainly upland dry heaths dominated by shrubs; in winter, both species make greater use of moist transitional habitats. Although the two species differ in their patterns of resource use, these differences may be altered through interspecific and intraspecific interactions.