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1.
《Ostrich》2013,84(2):173-176
The Cape Vulture Gyps coprotheres is an Endangered colonial cliff-nesting species that is typically cited as monogamous. Observations of wild Cape Vulture colonies note extra-pair breeding activities but homosexual activity has never been confirmed. Observations of breeding behaviours within a captive colony were conducted at VulPro’s breeding facilities in South Africa The captive breeding programme included 10 breeding pairs and a total of 41 non-releasable, individually recognisable, and genetically sexed subadults or adults. Observations were conducted over the 2014 breeding season as part of a study investigating the social and rearing conditions of chicks intended for release in a population supplementation programme. A high percentage of total colony copulation attempts (22%) were extra-pair copulations but only 23 interactions resulted in cloacal contact or possible sperm transfer. Four paired males formed extra-pair relationships, two of which were homosexual.  相似文献   
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The Bearded Vulture Gypaetus barbatus occurs throughout its range in small and dwindling population fragments with limited genetic differentiation between populations, suggesting that the species might be managed as a single entity. The numbers of East and Southern African Bearded Vultures included in previous studies were small, so we determine the genetic variation within, evolutionary placement of and connectivity among sub‐Saharan African populations. Mitochondrial DNA fragment analyses detected little or no differentiation between populations in Ethiopia and Southern Africa, with reduced haplotype diversity in Southern Africa compared with populations in the Northern Hemisphere. The results inform conservation management of this species globally and locally, and offer guidelines for translocations should populations continue to decline.  相似文献   
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Multimeric index based on fish composition was used to assess integrity of shallow and wadeable streams of lower Himalayas in temperate and subtropical ecoregions. Streams were surveyed for biotic and abiotic sampling during base flow periods in pre and post monsoon seasons in 2007 and 2008. Twenty three metrics were computed based on taxonomic richness, trophic composition, habitat preferences, abundance, stress tolerance and species origin attributes of 19 fish species. Candidate metrics were analyzed for efficiency to discriminate degraded sites from non-degraded and redundancy analysis, which sorted 71% of omnivore individuals (excluding intolerant species), 40% of intolerant individuals, 44% of herbivore individuals (excluding benthic species), abundance and 44.5% of non-native individuals as potential metrics. IBI values at forest, agriculture and urban zones were ranged between (max–min) 9.9–3.22, 6.18–2.49 and 4.43–0.69 respectively. Results suggested that poor ecological conditions in streams were generally related to drainage of urban sewage and habitat fragmentation while agriculture land use seems to have moderate impact on ecological integrity of the streams. Less urbanized upstream with grasslands and forests as land use, showed excellent to good ecological integrity of the streams. Proposed index was able to distinguish varying degrees of human impact on ecological integrity of streams and thus index could be used as valuable tool for bioassessment of regional flowing water resources.  相似文献   
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喜马拉雅旱獭种群微卫星变异及遗传多样性   总被引:1,自引:1,他引:0  
为了解不同地理种群喜马拉雅旱獭(Marmota himalayana)的种群数量变化并探讨其内在的遗传学机制,通过构建部分基因组文库的方法筛选出8个高变异微卫星位点,根据微卫星位点的测序结果设计相应引物,PCR扩增检测了青藏高原4个地理种群(德令哈、乌兰、沱沱河、安多)喜马拉雅旱獭的遗传多态性及其种群结构.研究结果显示:8个位点在喜马拉雅旱獭种群中均为高度多态,观察等位基因数、有效等位基因数、多态信息含量分别为4.75、3.033 2、0.610 2;喜马拉雅旱獭种群总的期望杂合度和观察杂合度分别为0.670、0.699;3个喜马拉雅旱獭种群显著(P<0.05)或极显著(P<0.01)偏离H-W平衡状态,且这些偏离平衡的位点均由杂合过度导致(FIS<0);喜马拉雅旱獭种群的部分位点已经偏离了突变-漂移平衡.结论:筛选出的8个微卫星位点适合于喜马拉雅旱獭种群遗传多样性的研究,所研究的喜马拉雅旱獭种群有较高的遗传多样性,安多地理种群在近期可能经历过瓶颈效应,种群数量曾经下降.  相似文献   
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ABSTRACT.   We designed a system of solar-powered video cameras that transmitted images via telemetry to a monitor. This system allowed us to study the breeding behavior of the Bearded Vulture ( Gypaetus barbatus ) in the Pyrenees (northeastern Spain). From 2000 to 2004, 12 nests in seven territories were equipped with video cameras. To avoid disturbing the birds, equipment was installed 3–8 weeks before egg-laying. The acceptance rate was 75%. No decline in productivity was observed for nests monitored with video cameras compared to control nests. The cameras enabled us to document egg-laying, hatching asynchrony, the nestlings' diet, and the parents' breeding behavior from distances of 2–3 km, although technical problems temporarily interrupted the transmission of images. Video cameras can be used successfully to study the Bearded Vultures, and probably other cliff-nesting raptors, without reducing productivity.  相似文献   
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A new species of the genus Protobothrops Hoge Romano-Hoge, 1983, was described from Jilong County, southern Tibet, China, and Chungthang, northern Sikkim, India. It differs from congeners by the following characters: 1) relatively large body size(total length up to 1510 mm); 2) dorsal scale rows 25–25–19; 3) except for the smooth outermost row, dorsal scales are weakly keeled; 4) relatively high number of ventral(198–216) and subcaudal(65–76 pairs) scales; 5) 7–8 supralabials; 6) 11 to 13 infralabials; 7) dorsal head uniform dark brown, laterally a reddish-brown obscure postocular streak; 8) dorsum of trunk and tail olive, with distinct black edged red brown transverse bands across the body and tail; and 9) eye from bright brown and reddish brown to mildly brown. The new species was also observed from the Haa Valley in western Bhutan.  相似文献   
8.
Mean hemoglobin (Hb) concentration of about 3 500 subjects derived from 17 studies of Himalayan highlanders (Tibetans, Sherpas, and Ladakhis) was compared with lowlanders (Chinese Han, Indian Tamils) lived in the Himalayas, and European climbers during Everest expeditions as well as Andean natives. The results found that Hb concentration in Himalayan highlanders was systemically lower than those reported for Andean natives and lowland immigrants. These comparative data demonstrated that a healthy native population may successfully reside at high altitude without a significant elevation in Hb, and the lower Hb levels of Himalayan highlanders than those of migrated lowlanders and Andean natives are an example of favourable adaptation over the generations. In addition, excessive polycythemia has frequently been used as a marker of chronic mountain sickness (CMS). Altitude populations who have a higher Hb concentration also have a higher incidence of CMS. The low Hb in Himalayans suggested as showing adaptation over many generations in Tibetan stock. Recent work in Tibet, suggested that Tibetans there may have adapted to high altitude as a result of evolutionary pressure selecting for genes which give an advantage at altitude. All of the population genomic and statistical analysis indicated that EPAS1 and EGLN1 are mostly likely responsible for high altitude adaptation and closely related to low Hb concentration in Tibetans. These data supported the hypothesis that Himalayan highlanders have evolved a genetically different erythropoietic response to chronic hypoxia by virtue of their much longer exposure to high altitude.  相似文献   
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During the last decades, the critically endangered Hooded Vulture Necrosyrtes monachus has strongly declined across its African range. Although direct persecution has been suggested as a major cause of this decline, little is known about the impact of humans on reproductive output in West Africa. We studied the impact of human activities on the reproductive output of Hooded Vultures in the Garango area of Burkina Faso. Twenty and 56 nesting attempts were monitored, respectively, during the breeding season in 2013/14 and 2014/15, to determine reproductive success and identify causes of nest failure. Annual breeding success varied between 0.68 and 0.71 chicks fledged per breeding pair per year and productivity was assessed at 0.57 chicks fledged per territorial pair in 2014/15. The main threats imposed by humans were poaching of eggs, chicks and collection of nest materials, leading to 20% (13 out of 64 breeding attempts) of nest failures over the two years. An additional important reason for nest failure was the pruning and (partial) cutting of nest trees. Despite this high level of human interference, we found that Hooded Vulture nest success increased with proximity to human settlements, probably because breeding vultures benefit from protection by people against persecution and disturbance.  相似文献   
10.
Two hypotheses have been proposed to link population regulation to density‐dependent changes in demographical parameters: the habitat heterogeneity hypothesis (HHH) states that, as population density rises, an increasing proportion of individuals are forced to occupy low‐quality territories, which provokes a decline in average per‐capita survival and/or productivity although some individuals show no decline in fecundity; and the individual adjustment hypothesis (IAH), which suggests that increased densities lead to reductions in survival and/or fecundity by enhancing agonistic interactions, which affect all individuals to a similar extent. However, density‐dependent effects can be affected by density‐independent factors (DIF), such as weather. We test the effects of density dependence on annual reproductive success in Griffon Vultures Gyps fulvus at four spatial scales, nest‐site, cliff, colony and metacolony, in northern Spain from 2008 to 2015. Our results showed most support for the HHH at all scales. At the colony and cliff scale, IAH and DIF had similar importance, whereas there was little evidence of IAH at the metacolony and the nest scale. The best protected eyries (caves, potholes and sheltered ledges) produced the most fledglings and were used preferentially, whereas low‐quality eyries (exposed ledges or open crevices) were used only when the number of breeders increased. The significant interaction between breeding failure and density found for the more exposed eyries suggests that at higher densities, breeding pairs are forced to use poorer nesting areas, and the negative effect of density at the cliff scale could be due to the combined effect of a higher proportion of pairs using low‐quality eyries and the negative effect of rainfall.  相似文献   
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