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161.
The pygmy rabbit ( Brachylagus idahoensis ) is a secretive, obligate sagebrush-steppe resident of the Intermountain West and is one of two rabbits in North America that digs its own burrows. Although the pygmy rabbit has a recorded home range of 0.21–67.9 ha in relatively high sagebrush cover (21%–36%), they spend much of their time within 30–100 m of a burrow system. Due to big sagebrush cover in preferred habitat and the secretive behavior of pygmy rabbits, it is often difficult to study this leporid through direct observation. We used remote cameras to document pygmy rabbit activity at burrow systems in south central Utah from 2006 to 2008. We analyzed photographs from remote cameras for daily and seasonal patterns of activity. Our results suggested that time of day and season were important influences on activity level, while year and site were less so. Pygmy rabbits were active during all time periods of the day, but the greatest activity occurred in the morning, except during winter. Numerous other species were recorded by remote cameras, including other leporids, birds, rodents, reptiles, and terrestrial predators. Remote cameras are a valuable tool in understanding pygmy rabbit behavior, in addition to confirming rabbit presence in areas of interest. 相似文献
162.
A total of 3291 resident deer hunters returned questionnaires distributed at checking stations in fall 1989 and 1990 providing opinions and management data concerning the Utah rifle hunt. Hunters reported hunter crowding and too few big bucks as critical reasons for possibly choosing to quit deer hunting in Utah. Indeed, hunter age structure and measured satisfaction suggested a negative future trend in hunter participation. Results suggested the adoption of several hunter-preferred management options would increase satisfaction, motivation, and success. 相似文献
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Diane W. Davidson William D. Newmark Jack W. Sites Jr. Dennis K. Shiozawa Eric A. Rickart Kimball T. Harper Robert B. Keiter 《西北部美国博物学家》2011,56(2)
Congress is currently evaluating the wilderness status of Bureau of Land Management (BLM) public lands in Utah. Wilderness areas play many important roles, and one critical role is the conservation of biological diversity. We propose that objectives for conserving biodiversity on BLM lands in Utah be to (1) ensure the long-term population viability of native animal and plant species, (2) maintain the critical ecological and evolutionary processes upon which these species depend, and (3) preserve the full range of communities, successional stages, and environmental gradients. To achieve these objectives, wilderness areas should be selected so as to protect large, contiguous areas, augment existing protected areas, buffer wilderness areas with multiple-use public lands, interconnect existing protected areas with dispersal and movement corridors, conserve entire watersheds and elevational gradients, protect native communities from invasions of exotic species, protect sites of maximum species diversity, protect sites with rare endemic species, and protect habitats of threatened and endangered species. We use a few comparatively well-studied taxa as examples to highlight the importance of particular BLM lands. 相似文献
164.
Dennis D. Austin 《西北部美国博物学家》2011,44(1)
Vegetal composition was determined during 1974 and 1984 using 60 permanent 50 m 2 plots within a mature pinyon-juniper community in northeastern Utah. Results indicated that not only was there little significant change in community composition, but with many species frequency and density remained nearly the same during the decade. 相似文献
165.
Low-density grasshopper populations were sampled at 15 pairs of rangeland sites in south central Idaho. One site of each pair had not been grazed by livestock for at least 10 years. Grazed sites were managed under normal grazing regimes established by the Bureau of Land Management. Mean grasshopper density was higher on ungrazed sites than on grazed sites. Proportions of Melanoplus sanguinipes were higher on ungrazed sites than on grazed sites and were higher on annual grasslands than on other vegetation types. Effects of grazing appeared to be independent of vegetation type. Proportions of Comhpocerinae, a subfamily of grasshoppers that feeds almost exclusively on grasses, were affected by vegetation type, but not grazing. Crested wheatgrass seedings supported the highest proportions of Gomphocerinae. Proportions of Oedipodinae were affected by grazing and vegetation type. Higher proportions of Oedipodinae were found on grazed sites than on ungrazed sites, and on sagebrush/grass sites than on annual grasslands. Results indicate that livestock grazing during drought conditions tends to reduce grasshopper populations in southern Idaho rangeland. 相似文献
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Epigenetics and disease: Altered states 总被引:8,自引:0,他引:8
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