Forest Grouse and Ptarmigan

Abstract

Abstract The Kluane system harbors five species of grouse. Two species, spruce grouse (Falcipennis canadensis) and ruffed grouse (Bonasa umbellus), inhabit forest year-round. Three species of tundra grouse, willow ptarmigan (Lagopus lagopus), white-tailed ptarmi­ gan (L. leucurus), and rock ptarmigan (L. mutus), inhabit the alpine and subalpine above treeline in the Shakwak Valley most of the year. Willow ptarmigan descend into the open forest from October to March. All grouse are almost exclusively herbivores; females dur­ ing egg laying and young chicks also eat a variety of invertebrates. Spruce grouse are conifer specialists, foraging principally on spruce and pine in winter and on forbs and leaves, fruits, and seeds of shrubs in summer and autumn (Boag and Schroeder 1992). Spruce grouse spend significant amounts of time foraging on ground vegetation in sum­ mer and thus might compete with hares for food during the breeding season. Ruffed grouse feed principally on buds and leaves of deciduous trees (aspen, bog birch) and shrubs and forbs seasonally (Rusch et al. 2000). Ptarmigan feed on willow buds and leaves through­ out the year and on flowers, leaves, seeds and berries of sedges, ericaceous shrubs, and mosses in season (Braun et al. 1993, Hannon et al. 1998). Both forest grouse and ptarmigan form part of the herbivore trophic level year-round in Kluane, as their wide-ranging predators (goshawk, golden eagle, harrier, coyote, lynx, fox, wolverine, wolf) hunt in both forest and adjacent alpine areas.