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2000: ivlowat et al. 2000). However. Koehler (1990) suggested that a diet of red squirrels alone <br />might not be adequate to ensure Ivnx reproduction and survival of kittens. <br />Little research on lynx diet specific to the southern portion of its range has been conducted. <br />except in Washington (Koehler et al. 1979; Koehler 1990). Southern populations of lynx may <br />prey on a wider diversity of species than northern populations because of lower average hare <br />densities and differences in small mammal communities. In areas characterized by patchy <br />distribution of lynx habitat. lynx may prey opportunistically on other species that occur in <br />adjacent habitats, potentially including white-tailed jackrabbit (Lepus toWrasendii), black-tailed <br />jackrabbit (Lepus californicus), sage-grouse (Centrocercus urophasianus)_ and Columbian sharp- <br />tailed ;grouse M nipanuchus phasianellus) (Quinn and Parker 1987: Lewis and Wenger 1998). <br />In northern regions, when bare densities decline, the lower quality diet causes sudden decreases <br />in the productivity of adult female lynx and decreased survival of kittens, which causes the <br />numbers of breeding lynx to level off or decrease (Nellis et al. 1972; Brand et al. 1976; Brand <br />and Keith 1979, Poole 1994, Slough and Mowat 1996; O'Donoghue et al. 1997). Relative <br />densities of snowshoe hares at southern latitudes are generally lower than those in the north, and <br />differing interpretations of the population dynamics of southern populations of snowshoe hare <br />have been proposed (Hodges 2000b). <br />Snowshoe hares have evolved to survive in areas that receive deep snow (Bittner and Rongstad <br />1982). Primary forest types that support snowshoe hare are,4bies lasiocar pa (subalpine fir), <br />Picea enlelmannii (Engelmann spruce), Pseudotsar-a men_iesii (Douglas-fir), and PiMIS <br />contorta (lodgepole pine) in the western United States. and spruce/fir, pine, and deciduous <br />• forests in the eastern United States (Hodges 2000b). Within these habitat types, snowshoe hares <br />prefer stands of conifers with shrub understones that provide forage, cover to escape predators, <br />and protection during extreme weather (Wolfe et al. 1982; Monthey 1986; Koehler and Aubrey <br />1994). Hares' use of habitat is correlated with understory cover (Hod(_,es 2000a). Early <br />successional forest stages generally have greater understory structure than do mature forests and <br />therefore support higher hare densities (Hodges 2000a, b). However, mature forests can also <br />provide snowshoe hare habitat as openings are created in the canopy when trees succumb to <br />disease, fire, wind, ice, or insects, and the understory develops (Buskirk et al. 2000b). <br />Lynx seem to prefer to move through continuous forest, using the highest terrain available such <br />as ridges and saddles (Koehler 1990, Staples 1990. Cover is important to lvnx when searching <br />for food (Brand et al. 1976) but lynx often hunt along edges (Mowat et al. 2000). Kesterson <br />(1988) and Staples (1990 reported that lvnx hunted along the edges of mature stands within a <br />burned forest matrix and Major (1989) found that lynx hunted along the edge of dense riparian <br />willow stands. Lvnx have been observed (via snow tracking) to avoid large openings (Koehler <br />1990; Staples 1990 durin,.,, dailv movements within the home range. <br />Den site selection - Lvnx use large %voody debris. such as downed logs. root wads and windfalls, <br />to provide dennintg sites with security and thermal coyer for kittens (McCord and Cardoza 195'; <br />Koehler 1990: Koehler and Brittell 1990: iviowat et al. 2000: Squires and Launon 2000). During <br />the first fe%v months of life. kittens are left alone at these sites when the female lynx hunts. <br />Downed logs and overhead cover provide protection of kitten, from predators. such as owls. <br />hawvks and other cam),, ores during this period. <br />