 Wysłany: Nie 10:57, 20 Mar 2011 Temat postu: California spotted owl air max chaussures |
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| California spotted owl selection for high canopy cover was more consistent for roosting sites than nesting sites,air max chaussures according to data from the central Sierra Nevada and southern California [45]. In the central Sierra Nevada, California spotted owl roost plots occurred in mixed-conifer forest dominated by trees larger than 12-inches (30 cm) DBH significantly (P<0.001) more than random sites [71]. In coniferous forests of Arizona, Mexican spotted owl roost plots had greater (P≤0.05) canopy cover, coarse woody debris, and tree and snag densities than random plots [61]. In Saguaro National Park, roost plots had greater canopy cover, more trees,authentic nfl jerseys, more vegetation layers, and greater basal areas than random plots. In addition, trees in the roost plots were taller and had larger DBH than those on random sites (P≤0.05) [26]. However, Mexican spotted owl roost trees are generally smaller than nest trees [27]. Spotted owl roosting and nesting habitat are also similar at larger scales.[56]
In mixed-conifer and Douglas-fir forests of southwestern Oregon, northern spotted owl roost sites averaged 45 feet (13.7 m) above ground and ranged from ground level to 256 feet (78 m). Roost trees averaged 24 inches (61 cm) DBH and 83 feet (26 m) tall. These roost sites averaged 69% overhead cover [10]. Spotted owls often roost in Douglas-fir, but several species are used. In mixed-conifer and Douglas-fir forests of southwestern Oregon,replica cartier watches 46% of northern spotted owl roost sites were in Douglas-fir. Thirteen percent of roosts occurred in western hemlock and 9% were in western redcedar. Northern spotted owls also roosted in bigleaf maple (Acer macrophyllum), incense-cedar (Calocedrus decurrens), grand fir, giant chinkapin (Chrysolepis chrysophylla), Pacific madrone (Arbutus menziesii), and canyon live oak [10]. In Saguaro National Park about 60% of Mexican spotted owl roosts were in Douglas-fir. Gambel oak, southwestern white pine, ponderosa pine, New Mexico locust (Robinia neomexicana), and a white pine snag were also used for roosting [26]. In the upper Gila Mountains, 54% of roosts were in Douglas-fir and 21% were in Gambel oak. Although mean prey biomass of nesting northern spotted owls was generally higher than that of nonnesting owls in coniferous habitats of the Olympic peninsula and eastern Cascade Range in Washington, the difference was only significant (P<0.05) in 2 of 21 territories? [73]. Nest success in coniferous forest,ed hardy jeans oak woodland, and riparian deciduous habitats of the Sierra National Forest was not related to the northern flying squirrels, proportion of biomass[74]. |
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