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101.
Wildlife corridors, protected bands of suitable habitat linking core populations of plants and animals, are seen as the best solution to the problem of habitat fragmentation. A corridor between two wildlife refuges was identified in the communal lands of Zimbabwe. Results of tracking the current preferred migration of bull elephants between the two refuges using radio collars were combined with a GIS analysis to examine the zone where conservation of habitat would have least impact on current activities within the communal lands. A suitable corridor was identified using least‐cost analysis allowing for the improved conservation of the elephants and therefore potentially increasing the benefits to local residents by both reducing human/elephant conflict and increasing income from sport hunting and tourism in the region. Recent political violence in the corridor region, the illegal killing of elephants and the loss of suitable habitat makes the implementation of this corridor unlikely. 相似文献
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103.
Natural populations of the endangered western barred bandicoot (Perameles bougainville) now exist on only two islands in Shark Bay, Western Australia. Our aim was to investigate genetic diversity in natural,
reintroduced, and captive populations of the bandicoots and to assess the extent of divergence between the populations. The
contemporary isolation of the natural populations has resulted in heterogeneity of allele frequency between the islands, which
has acted to maintain a higher combined diversity than would be expected from either population on its own. These findings
highlight how remnant island populations can act as genetic reservoirs to maximize diversity for reintroductions into a species
former range. Although diversity is high between island populations, diversity within populations, based on six microsatellite
loci, are amongst the lowest ever recorded for populations of marsupials. The mtDNA sequence data indicate that the two remaining
natural populations show only minor divergence from each other, with the five haplotypes separated by just single base pairs.
The reintroduced population and captive colonies show evidence for the loss of diversity related to genetic drift operating
on small isolated populations. 相似文献
104.
Michael J. Schmidt 《Zoo biology》1982,1(2):141-147
Studies of Asian elephant reproduction at the Washington Park Zoo in the areas of the estrous cycle, semen collection, bull elephant management and health care, pregnancy, and pheromones have yielded sufficient information to attempt repeated artificial insemination (AI) at the time of ovulation. While no pregnancy has been achieved to date, with the information now at hand AI can be expected to become a practical technique for breeding elephants in captivity. 相似文献
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107.
Western lowland gorillas (Gorilla gorilla gorilla) are designated as critically endangered and wild populations are dramatically declining as a result of habitat destruction, fragmentation, diseases (e.g., Ebola) and the illegal bushmeat trade. As wild populations continue to decline, the genetic management of the North American captive western lowland gorilla population will be an important component of the long‐term conservation of the species. We genotyped 26 individuals from the North American captive gorilla collection at 11 autosomal microsatellite loci in order to compare levels of genetic diversity to wild populations, investigate genetic signatures of a population bottleneck and identify the genetic structure of the captive‐born population. Captive gorillas had significantly higher levels of allelic diversity (t7 = 4.49, P = 0.002) and heterozygosity (t7 = 4.15, P = 0.004) than comparative wild populations, yet the population has lost significant allelic diversity while in captivity when compared to founders (t7 = 2.44, P = 0.04). Analyses suggested no genetic evidence for a population bottleneck of the captive population. Genetic structure results supported the management of North American captive gorillas as a single population. Our results highlight the utility of genetic management approaches for endangered nonhuman primate species. 相似文献
108.
Jody Gunn Dawn Hawkins Richard F. W. Barnes Fredrick Mofulu Rachel A. Grant Guy W. Norton 《African Journal of Ecology》2014,52(2):129-137
Long‐term solutions to crop raiding by elephants (Loxodonta africana) should be based on an understanding of their behaviour and ecology. The real and perceived risks from humans have been shown to affect elephant behaviour. This is evidenced by elephants predominantly raiding crops at night, avoiding the height of human activity. If such human avoidance behaviours are apparent, it might also be expected that elephants avoid risks associated with higher visibility and increased human activity as may occur during the full moon. However, elephant nocturnal crop‐raiding behaviour in relation to lunar cycles has largely been a neglected factor in studies of human–elephant interactions. In this study around Mikumi National Park, Tanzania, we apply circular statistics in this context for the first time to show a significant decrease in crop raiding during the full moon and apply this method retrospectively to data from another site in West Africa with similar results. Additionally, a greater proportion of farms raided was guarded during the full moon than any other moon phase. Our results indicate that variations in crop raiding with lunar phase could be a general feature of elephant behaviour and thus could be used to design and time mitigation efforts. 相似文献
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卧龙圈养大熊猫遗传多样性现状及预测 总被引:2,自引:0,他引:2
以中国最大的大熊猫圈养种群—四川卧龙中国大熊猫保护中心的圈养种群为对象,以8个大熊猫微卫星位点为分子标记, 探讨了大熊猫圈养种群的遗传多样性, 并与邛崃野生种群及其他7个濒危物种进行比较。微卫星数据表明, 圈养种群的遗传多样性水平(A=5.5, He =0.620, Ho=0.574) 低于邛崃野生种群(A=9.8,He=0.779,Ho=0.581),但高于其他7 个濒危物种的种群(He=0.13~0.46)。在此数据的基础上对未来100个世代内圈养种群遗传多样性的变化情况做出了预测。结果表明假设种群数量比现在扩大一倍, 经历100个世代后也只会使平均等位基因数少减少0.4。因此继续增加野生个体对保持遗传多样性的意义已经不大, 建议该圈养种群的保护策略应将重点放到制定更有效的繁殖计划以避免近交上。 相似文献