Seasonal diets of Vancouver Island (Canada) marmots, Marmota vancouverensis [Régimes alimentaires des marmottes de l'île de Vancouver (Canada), M. vancouverensis].

Résumé

The diet of Vancouver Island Marmots (Marmota vancouverensis) was examined by fecal analysis at three subalpine colonies on four occasions between late May and mid-September. Two additional, high-elevation colonies were examined in late May only. Diets were similar among colonies but showed seasonal shifts. Diets were more variable among sites in late May than later in the summer, possibly reflecting site-specific availability at a time when food supply is limited. In late May Phlox diffusa and Carex sp. were important at all colonies but Danthonia intermedia, Lupinus latifolius, and sedge glumes were dominant at specific colonies. Later in the summer Lupinus and Eriophyllum lanatum were the major foods at all colonies. As summer progressed the proportion of graminoids in the diet declined and the proportion of forbs increased. Vancouver Island Marmots in the subalpine appear to specialize on relatively few food species.