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101.
Very little is known about prey selection by the Indian tiger Panthera tigris tigris in tropical dry deciduous forests or in wild herbivore-depleted habitats with high livestock pressures. We undertook a short-term study in a large south Indian tiger reserve and examined two intensive study areas (SA's) from October 1998 – June 1999. In each area, herbivore sightings were recorded, scats were collected, and wild prey and livestock kills documented. Chital, wild boar and sambar were the most abundant among the wild herbivores in the study area. Scat analysis revealed wild boar (Sus scrofa) being the most common prey followed by chital (Axis axis) and sambar (Rusa unicolor). Livestock comprised less than 7% of diet intake. Here, the tigers consumed a lower mean prey mass (56.3 kg) than in other reserves. Our study suggests that in tropical dry deciduous forests with low natural prey density, smaller prey species, and high livestock biomass, tigers preferentially kill smaller prey and generally avoid livestock predation.  相似文献   
102.
The Amur tiger, Panthera tigris altaica, is a highly endangered felid whose range and population size has been severely reduced in recent times. At present, the wild population is estimated at 490 individuals, having rebounded from the 20–30 tigers remaining following a severe bottleneck in the 1940's. The current study presents preliminary data on the patterns and levels of genetic variation in the mitochondrial DNA control region using DNA extracted from non-invasively sampled faecal material, collected throughout the entire range of P. t. altaica in the Russian Far East. Analysis of 82 scat samples representing at least 27 individuals revealed extremely low levels of CR haplotype diversity, characterized by a single widespread haplotype (96.4%) and two rare variants, each differing by a single step within the hypervariable I (2.4%) and central conserved regions (1.2%), respectively. A comparison with previous data on cytochrome bvariation in 14 captive individuals revealed a potentially greater amount of genetic variation represented in captivity relative to that found in the wild population. The extremely low levels of mitochondrial DNA variation in the wild population is discussed in light of the demographic processes that might have shaped these patterns as well as the potential bias introduced through analysis of fecal samples. These results highlight the continuing need to assess levels of genetic variation even in recovering populations that are increasing in number and underscore the important role that captive breeding programs may play in preserving remnant genetic diversity of endangered species.  相似文献   
103.
基于线粒体控制区序列探讨豹属分子系统发生关系   总被引:1,自引:0,他引:1  
为探讨豹属Panthera物种间的系统发生关系,测定了虎Panthera tigris、豹Panthera pardus和雪豹Panthera uncia的线粒体控制区全序列,结合其它5种猫科动物的同源序列进行分析。分别采用最大似然法(Maximum Likelihood,ML)、邻接法(Neighbor-Joining,NJ)和贝叶斯法(Bayesian Inference,BI)重建了豹属物种的分子系统发生树。结果表明:豹属除由传统的物种狮Panthera leo、虎P.tigris、豹P.pardus、及美洲虎P.onca组成外,雪豹P.uncia应并归于豹属,不支持将雪豹另立为雪豹属Uncia的观点;云豹Neofelis nebulosa与豹属具有最近的亲缘关系而构成其姊妹群物种;云豹与豹属Panthera各物种间的系统发生关系为:云豹(豹(虎(狮(美洲豹、雪豹))))。  相似文献   
104.
The jaguar (Panthera onca), the largest felid in the American Continent, is currently threatened by habitat loss, fragmentation and human persecution. We have investigated the genetic diversity, population structure and demographic history of jaguars across their geographical range by analysing 715 base pairs of the mitochondrial DNA (mtDNA) control region and 29 microsatellite loci in approximately 40 individuals sampled from Mexico to southern Brazil. Jaguars display low to moderate levels of mtDNA diversity and medium to high levels of microsatellite size variation, and show evidence of a recent demographic expansion. We estimate that extant jaguar mtDNA lineages arose 280 000-510 000 years ago (95% CI 137 000-830 000 years ago), a younger date than suggested by available fossil data. No strong geographical structure was observed, in contrast to previously proposed subspecific partitions. However, major geographical barriers such as the Amazon river and the Darien straits between northern South America and Central America appear to have restricted historical gene flow in this species, producing measurable genetic differentiation. Jaguars could be divided into four incompletely isolated phylogeographic groups, and further sampling may reveal a finer pattern of subdivision or isolation by distance on a regional level. Operational conservation units for this species can be defined on a biome or ecosystem scale, but should take into account the historical barriers to dispersal identified here. Conservation strategies for jaguars should aim to maintain high levels of gene flow over broad geographical areas, possibly through active management of disconnected populations on a regional scale.  相似文献   
105.
本研究整理了2015-2016年三江源区曲麻莱县、治多县和囊谦县的人兽冲突记录,并对主要肇事物种和人兽冲突的时间分布、地点分布以及受损类型的分布进行了统计分析。结果显示:(1)主要肇事野生动物依次为狼(978起,64.13%)、棕熊(117起,7.67%)、雪豹(5起,0.33%)和野牦牛(3起,0.20%),其余422起冲突(27.67%)未记录肇事野生动物;(2)人兽冲突时间分布不稳定,其高发期在不同年份不同地区都有所不同,总体来看,每年的1月、2月和12月棕熊和狼引起冲突较少,高峰期通常为6-9月;(3)从地区分布看,人兽冲突热点区域是曲麻莱县和治多县,特别是曲麻莱县秋智乡和麻多乡,治多县治渠乡、多彩乡、立新乡和扎河乡,曲麻莱县和治多县交接区域是人兽冲突高发区,囊谦县人兽冲突整体相对较轻;(4)从受损类型看,对牛的攻击和伤害是最主要的受损类型(749次,79.94%),明显多于对羊(56次,5.98%)和马(24次,2.56%)造成伤害的冲突,以及对房屋和家具等其它财产造成破坏的冲突(108起,11.53%)。本研究结果为三江源生态保护和国家公园建设制定更有效的预防和缓解人兽冲突的措施等提供了可靠依据。  相似文献   
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108.
Although the anatomy of the domestic housecat has been examined in meticulous detail, comparative observations on the anatomy of the larger wild cats is scant and information about particularities in their cranial complexes rarer still. In the course of dissecting sets of masticatory muscles in five large felids, all older zoo animals, we had the opportunity to note muscular attachments in the head and jaw apparatus that appeared significantly broader and more distal in their insertion sties than expected. Further investigation may determine whether these masticatory peculiarities are functional adaptations of felids, or instead are associated in some manner with the specialized diets large felids receive in captive environments. Zoo Biol 16:187–191, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
109.
吉林珲春自然保护区东北虎捕食家畜研究   总被引:1,自引:0,他引:1  
东北虎在中国已经极度濒危,随着位于中俄朝三国边境地区的吉林珲春自然保护区在2001 年底的建成,对虎的保护初见成效。然而保护区内虎频繁捕食家畜,引发了当地居民的不满。为了减缓人虎冲突,寻找东北虎捕食家畜的有关规律,作者开展了东北虎捕食家畜的相关研究。从2001 年12 月至2007 年底,共计有126 起,204 头家养动物被虎袭击,且呈现逐年上升的趋势。家畜被袭击主要发生在每年的4 ~ 9 月,没有发现明显的对家畜种的偏好。利用GIS 和回归分析表明:1)虎通常不袭击离开村庄小于1 km 的家畜;2)人为干扰对家畜的被食用率和虎移动家畜尸体的行为都有显著影响;3)共计有约16 079 kg 的家养动物肉被虎食用,造成损失76084 美元;4)对虎袭击地点生态变量的分析表明,东向和南向有更多的家畜被袭击;5)此外,虎多在较低的海拔和坡度、较高的郁闭度,靠近村庄和河流,远离道路等区域捕食家畜。清除套子和防止下套以增加有蹄类的密度对于减少虎捕食家畜非常重要。此外,减少虎袭击地点的人为干扰和改善对家畜的看护也非常关键。  相似文献   
110.
非洲狮(Pantheraleo)群处于不断的分裂-聚合过程,其亚群大小与原狮群大小以及诸如狮群捕食成功度、协作幼仔保护及狮群领域防卫等社会性因素有关。我们分析了南非一个保护区(Hluhluwe-Umfolozi公园)15年间的狮群大小,其成年雌狮和成年雄狮群的大小在保护区内呈显著性变化。在开放生境中雌狮结大群,而茂密植被生境中则结小群。雄狮群大小与植被类型无关,但在大的雌狮群分布区域发现大雄狮群。令人惊奇的是,作为幼狮成活率指标的幼狮群大小和雌狮平均幼仔数在保护区内没有显著性差异。我们认为,雌狮群大小的不同是对植被结构的适应,即在开放生境中大群有利于协作狩猎、育幼、共同保护幼仔、应对高强度群间领域防卫竞争。相反,茂密植被中,群间竞争很低,高密度植被覆盖有利于狩猎成功及补偿小狮群对幼仔保护的不足。雌狮平均幼仔数在整个保护区内没有变化,我们认为是由于开放生境和茂密植被对狮群大小起到相似的调节作用  相似文献   
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