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111.
Abstract: Many aquatic species in the arid southwestern United States are imperiled, persisting primarily in isolated, low-order streams that are increasingly vulnerable to stochastic disturbances. During 2003 and 2004, we surveyed 39 mountain canyons in southeastern Arizona, USA, for lowland leopard frogs (Rana yavapaiensis), a species that has declined in abundance and distribution across its range in the United States. We quantified habitat features at 2 spatial scales, canyon and pool, to identify features that distinguished sites inhabited by frogs from those uninhabited by frogs. Canyons inhabited by frogs had watersheds that averaged 8.1 km2 larger (SE = 2.52), pools that averaged 37.8 m3 greater (9.30) in volume, gradients that averaged 4.1% (1.40%) less steep, and locations that averaged 3.2 km closer (1.06) to the nearest valley stream than did uninhabited canyons. Plunge pools inhabited by frogs averaged 13.5% (5.66%) more perimeter vegetation, 11.2% (5.34%) more canopy cover, and 1.9 (0.60) more refuges than uninhabited pools. In general, canyons that provided more perennial water during dry summer months and plunge pools that provided more bank heterogeneity were more likely to be inhabited by frogs. Conservation of lowland leopard frogs and other aquatic species that inhabit xeric systems in the southwestern United States depends principally on maintaining riparian ecosystems that provide habitat for these species and the adjacent uplands that influence the structure and function of these systems. Therefore, both riparian areas and their adjacent uplands must be managed to maintain habitat for organisms that inhabit these rare and diverse ecosystems.  相似文献   
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祁连山地区是中国乃至全球雪豹(Panthera Unica)分布最集中、种群密度最高的地区之一,该地区的雪豹科学保护对于全球雪豹种群具有重要意义。了解祁连山国家公园牧民对雪豹保护的态度认知、探究影响牧民对雪豹保护态度的主要因素,对于保护国家公园生态系统的原真性、促进人与野生动物和谐共处具有重要意义。基于半结构式访谈对祁连山国家公园牧民进行了随机抽样调查,结果表明:(1)受访者认为狼(n=34, 91.89%)和雪豹(n=16, 43.24%)是最重要的两种致害野生动物;(2)所有受访者对雪豹保护均持积极态度;(3)受访者认为野生动物捕杀(n=14, 50.00%)和草场退化(n=9, 32.14%)是家畜面临的两大威胁因素;(4)“雪豹捕杀家畜”和“为家畜购买商业保险”是影响牧民对雪豹保护态度的关键因素(P<0.05)。为促进人与野生动物长期共存,需要各级政府以国家公园体制建设为契机,进一步加强科学研究,制定更加科学合理的野生动物保护与管理措施。  相似文献   
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Few data are available on the behaviour of leopards in the absence of competing large predators and human impact, both of which are believed to influence leopard activity and movements. Remote camera traps and global positioning system (GPS) collars were used to quantify leopard activity in the Cederberg Mountains, seasonal and sexual differences in their movements, and determine whether nocturnal hunting success was related to lunar activity. Seventy‐seven per cent of camera‐trap photographs were at night, with a strong male bias (69%) in captures. Daily displacement using one location per day suggested that males moved significantly further than females. However, multiple locations (≥6 per day) showed no difference because males moved in a more linear fashion, but not further each day, than females. In the Cederberg Mountains, an open rocky habitat with low human impact and no competing predators, leopards were predominantly nocturnal, mainly hunting diurnal prey species. Hunting success was low: leopards travelled long distances between kills, with nocturnal hunting success higher on darker nights.  相似文献   
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Kenya's Tsavo National Parks are a critical conservation area and the only wilderness corridor through densely populated human-dominated landscapes stretching from the East African coast to Lake Victoria, separating extensive undeveloped grasslands south of the equator from the undeveloped semiarid bushlands to the north. At nearly 21,000 km2, Tsavo is one of four lion strongholds in East Africa and part of Africa's most important populations of all other large African carnivores. To provide baseline data on the status of large carnivores, a track survey was undertaken in 2013. Lions and both hyaena species were widely distributed across both parks, while cheetahs and wild dogs were more patchily distributed. Spotted hyaenas were the most abundant, with an estimated population of 3,903 ± 514 (95% CI), followed by lion (706 ± 201), striped hyaena (679 ± 144), leopard (452 ± 98), cheetah (154 ± 74) and wild dog (111 ± 92). Tsavo's carnivores suffer from bushmeat poaching, illegal grazing and retaliatory killing, and increasing human numbers on its periphery. Given Tsavo's importance as a stronghold for lions and an ecological corridor, increased investment in effective protection is strongly recommended. Evaluating trends will require complementary techniques in light of intensive monitoring requirements.  相似文献   
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The snow leopard (Uncia uncia) is a rare carnivore living above the snow line in central Asia. Using universal primers for the mitochondrial genome control region hypervariable region 1 (HVR1), we isolated a 411‐bp fragment of HVR1 and then designed specific primers near each end of this sequence in the conserved regions. These primers were shown to yield good polymerase chain reaction products and to be species specific. Of the 12 snow leopards studied, there were 11 segregating sites and six haplotypes. An identification case of snow leopard carcass (confiscated by the police) proved the primers to be a useful tool for forensic diagnosis in field and population genetics studies.  相似文献   
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