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1.
Utah prairie dogs were transplanted onto the site of a former colony, located in Capitol Reef National Park, Utah. Shrubs on the site were significantly taller than those found on active colonies in similar habitat located on the Awapa Plateau. Therefore, the transplant site afforded a test of the hypothesis that shrub height is a major inhibitory factor affecting occupation of sites by prairie dogs. Four sites of 5 ha each were used. Vegetation treatments — rotobeating, railing, and 2,4 - D herbicide — were carried out on three of the sites and the fourth was used as a control. Shrub height and percent cover were significantly reduced on all three treatment sites. Posttreatment effects on the vegetation showed that the greatest percent moisture of the herbage was found on the railed site, followed by the herbicide, rotobeaten, and control sites. Measurements of the visual obstructions to prairie dogs showed that the rotobeaten site had the greatest visibility, followed by the railed, herbicide, and control sites. Prior to release of prairie dogs on the study area, 200 artificial burrows per treatment were dug, using a power auger. In early summer, 1979, 200 Utah prairie dogs were live - trapped near Loa, Utah. An equal number by sex and age class were released on each treatment. In 1979 a significantly higher number of animals reestablished on the rotobeaten site. In 1980 and 1981 the rotobeaten and railed sites had significantly higher prairie dog numbers than the other sites. Reproduction occurred on both the rotobeaten and railed sites in 1980 and 1981. Results indicated that, when transplanting animals onto sites of former colonies presently overgrown with shrubs, the chances of a successful transplant could be increased by first reducing shrub height and density.  相似文献   
2.
Native mushrooms play an important, though often underestimated, role in deer, elk, and caribou diets in North America. Mushrooms are often noted as an unusual or anomalous food in the diets of cervids; yet they often dominate diets in the late summer and fall in forested areas of western North America and throughout the year in the southeastern U.S. Mushrooms are particularly high in protein (16-19%), phosphorus (average 0.75%), and potassium (average 2%). Also, mushroom production is generally greatest in fall. Therefore, they are a highly nutritious food in late season when other native forages may marginally meet basal nutrient requirements of ungulates.  相似文献   
3.
Trends in age-specific, eviscerated carcass weights were determined for hunter-harvested yearling and two-year-old buck mule deer. Carcass weights declined over an 11-year period from two areas of similar management, but with independenly collected data sets. Carcass weights also declined between the opening and second weekends of the hunt. Management implications are discussed.  相似文献   
4.
Tame mule deer and elk were fed fresh alfalfa hay at night and given various alternate forages during the day. This schedule, simulating farmland depredation feeding, yielded consumption values for field-growing alfalfa hay.  相似文献   
5.
Rearing young ungulates for ecological studies is costly and time consuming. Doe-rearing mule deer ( Odocoileus hemionus ) fawns is a viable alternative to the common method of bottle-feeding. Fawns tamed while nurtured by their tractable dams showed no marked difference in tractability over bottle-reared orphans. The advantages of doe-rearing are better health for the young and convenience for the handler.  相似文献   
6.
Arteriovenous malformations in mice lacking activin receptor-like kinase-1   总被引:21,自引:0,他引:21  
The mature circulatory system is comprised of two parallel, yet distinct, vascular networks that carry blood to and from the heart. Studies have suggested that endothelial tubes are specified as arteries and veins at the earliest stages of angiogenesis, before the onset of circulation. To understand the molecular basis for arterial-venous identity, we have focused our studies on a human vascular dysplasia, hereditary haemorrhagic telangiectasia (HHT), wherein arterial and venous beds fail to remain distinct. Genetic studies have demonstrated that HHT can be caused by loss-of-function mutations in the gene encoding activin receptor-like kinase-1 (ACVRL1; ref. 5). ACVRL1 encodes a type I receptor for the TGF-beta superfamily of growth factors. At the earliest stage of vascular development, mice lacking Acvrl1 develop large shunts between arteries and veins, downregulate arterial Efnb2 and fail to confine intravascular haematopoiesis to arteries. These mice die by mid-gestation with severe arteriovenous malformations resulting from fusion of major arteries and veins. The early loss of anatomical, molecular and functional distinctions between arteries and veins indicates that Acvrl1 is required for developing distinct arterial and venous vascular beds.  相似文献   
7.
Two mule deer herds were studied on comparable, adjacent winter ranges in Utah. Significant differences in overwinter fawn survival were attributed to intensive predator control.  相似文献   
8.
The use of domestic grazers to shift the growth advantage toward shrubs is a commonly applied tool on winter ranges managed primarily for big game. Results from horses grazing in spring indicated grazing also benefits shrub survival, seedling recruitment, and reduced winter injury damage on some species of shrubs.  相似文献   
9.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Late summer diet composition of mule deer was determined daily within a mountain browse enclosure dominated by antelope bitterbrush. Palatable forages of low abundance were rapidly depleted, and bitterbrush continually composed over 50% of the diet, even at utilization exceeding 350 deer-days/ha. The relationship of bitterbrush forage production and deer-days use is discussed.  相似文献   
10.
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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