2008-06-12_GENERAL DOCUMENTS - C1980007 (3)

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The action area for the proposed action is the Mount Gunnison Lynx Analysis unit on the Paonia Ranger District of the Grand Mesa, Uncompahgre and Gunnison National Forests. The Service does not anticipate effects of the action to occur outside of this LAU. • STATUS OF THE SPECIES /CRITICAL HABITAT DESCRIPTION Species/Critical Habitat Description The lynx is a medium-sized cat with long legs; large, well-furred paws; long tufts on the ears; and a short, black-tipped tail (McCord and Cardoza 1982). The winter pelage of the lynx is dense and has a grizzled appearance with grayish-brown mixed with buff or pale brown fur on the back, and grayish-white or buff-white fur on the belly, legs and feet. Summer pelage of the lynx is more reddish to gray-brown (Koehler and Aubry 1994). Adult males average 10 kilograms (22 pounds) in weight and 85 centimeters (33.5 inches) in length (head to tail), and females average 8.5 kilograms (19 pounds) and 82 centimeters (32 inches) (Quinn and Parker 1987). The lynx's long legs and large feet make it highly adapted for hunting in deep snow. Life History Home range and dispersal - Lynx home range size varies by the animal's gender, abundance of prey, season and the density of lynx populations (Hatler 1988; Koehler 1990; Poole 1994; Slough and Mowat 1996; Aubry et al. 2000; Mowat et al. 2000). Documented home ranges vary from 8 to 800 square kilometers Q to 300 square miles) (Saunders 1963; Brand et al. 1976; Mech 1980; Parker et al. 1983; Koehler and Aubry 1994; Apps 2000; Mowat et al. 2000; Squires and Laurion 2000). Preliminary research supports the hypothesis that lynx home ranges at the • southern extent of the species' range are generally large compared to those in the core of the range in Canada (Koehler and Aubry 1994; Apps 2000; Squires and Laurion 2000). Lynx are capable of dispersing extremely long distances (Mech 1977; Washington Department of Wildlife 1993); for example, a male was documented traveling 616 kilometers (370 miles) (Brainerd 1985). Lynx disperse primarily when snowshoe hare (Lepus americanus) populations decline (Ward and Krebs 1985; Koehler and Aubry 1994; O'Donoghue et al, 1997; Poole 1997) Subadult lynx disperse even when prey is abundant (Poole 1997), presumably as an innate response to establish home ranges. Diet - Snowshoe hares (Lepus americanus) are the primary prey of lynx, comprising 35-97 percent of the diet throughout the range of the lynx (Koehler and Aubry 1994). Other prey species include red squirrel (Tamiasciurus hudsonicus), grouse (Bonasa umbellus, Dendrao, us spp., La- tis spp.), flying squirrel (Glaucomys sabrinus), ground squirrel (Spermophilus parrvu, S. richardsonii), porcupine (Erethricon dorsatum), beaver (Castor canadensis), mice (Peromyscus spp.), voles (Microtus spp.), shrews (Sorex spp.), fish, and ungulates as carrion or occasionally as prey (Saunders 1963; Van Zyll de Jong 1966; Nellis et al. 1972; Brand et al. 1976; Brand and Keith 1979; Koehler 1990; Staples 1995; O'Donoghue et al. 1998). Shenk (2004) reported snow-tracking results indicate the primary winter prey species are snowshoe hare and red squirrel, with other mammals and birds forming a minor part of the winter diet. During the cycle when hares become scarce, the proportion and importance of other prey species, • especially red squirrel, increases in the diet (Brand et al. 1976; O'Donoghue et al. 1998; Apps 4