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ABSTRACT. Numerous avifauna species face extinction on New Zealand's two main islands, owing largely to forest clearance and to introduced mammals. In response, New Zealand selects certain offshore islands for the relocation of threatened native birds, first purging them of mammalian predators. Over the past few decades, this procedure has evolved to become fairly successful. Protected habitat “islands” within mainland forested areas are also being created, but with success less certain. As historic habitats are lost, small biopreservation islands may become a standard mechanism for protecting threatened species, a process that can be termed the “miniaturization” of nature. 相似文献
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胶州湾滨海湿地的水禽多样性特征及保护 总被引：4，自引：0，他引：4
在利用相对数量法进行水禽种群调查基础上,研究胶州湾滨海湿地水禽区系的构成及多样性特征.研究区共有水禽9目20科140种,区系的地理成分以古北界鸟类占绝对优势,季节型成分以冬候鸟和旅鸟为主,生活型成分以涉禽为主;在不同季节研究区水禽的优势种群不同,夏季鸥科和鹭科为优势种群,春、秋季鴴科、鹬科、鹭科为优势种群,冬季雁鸭类、鸥科为优势种群.与青岛市陆禽、鸣禽、猛禽、攀禽等鸟类相比,胶州湾滨海湿地水禽的多样性指数、均匀度指数最高,说明胶州湾滨海湿地对青岛市鸟类多样性保护非常重要,生境破坏是当前水禽多样性保护面临的主要问题,提出了水禽生境保护的对策. 相似文献
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The Indian Thar Desert is one of the smallest and most densely populated deserts of the world but due to its geographical location it has high avian and plant diversity. Nearly 300 bird species have been identified. A 649-km long irrigation canal, the Indira Gandhi Nahar Project (IGNP), is changing the ecology of the Thar by bringing water to arid areas. Beside the main canal, nearly 8000 km of distribution channels have been built. A massive afforestation scheme along the canal has attracted many new animal and bird species. Expansion of agriculture, overgrazing by livestock, change in cropping pattern, development of seepage wetlands and introduction of exotic plants have greatly affected desert birds such as the endangered Great Indian BustardArdoetis nigriceps, the migratory Houbara BustardChlamydotis undulataand the endemic White-browed BushchatSaxicola macrorhyncha, while some species such as Common CraneGrus grusand Demoiselle CraneGrus virgoare spreading along the canal. This paper discusses the change brought about in the birdlife of the Thar by the development of IGNP and recommends urgent conservation measures. 相似文献
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DEREK A. SMITH 《Geographical review》2010,100(2):187-203
In this article I attempt to shed light on the relationships between indigenous communities and bird populations through research on hunting in five neighboring villages in western Panama. Over eight months, 59 households captured 1,584 birds using rifles, sling‐shots, traps, and other methods, resulting in a total yield of 252 kilograms. Although hunters captured more than 125 avian species, just four species account for more than half of the total harvest. The most important game bird is the great curassow (Crax rubra), followed by the great tinamou (Tinamus major) and crested guan (Penelope purpurascens). The type and quantity of avifauna captured varies significantly according to habitat and hunting strategy. The spatial distribution of bird kill sites is highly concentrated, with 62 percent of the harvest by weight captured within just 1 kilometer of the participating households. Even the more vulnerable species are encountered close to home, suggesting that overhunting has not occurred. 相似文献
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