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61.
Abstract: Unsustainable hunting of wildlife for food empties tropical forests of many species critical to forest maintenance and livelihoods of forest people. Extractive industries, including logging, can accelerate exploitation of wildlife by opening forests to hunters and creating markets for bushmeat. We monitored human demographics, bushmeat supply in markets, and household bushmeat consumption in five logging towns in the northern Republic of Congo. Over 6 years we recorded 29,570 animals in town markets and collected 48,920 household meal records. Development of industrial logging operations led to a 69% increase in the population of logging towns and a 64% increase in bushmeat supply. The immigration of workers, jobseekers, and their families altered hunting patterns and was associated with increased use of wire snares and increased diversity in the species hunted and consumed. Immigrants hunted 72% of all bushmeat, which suggests the short‐term benefits of hunting accrue disproportionately to “outsiders” to the detriment of indigenous peoples who have prior, legitimate claims to wildlife resources. Our results suggest that the greatest threat of logging to biodiversity may be the permanent urbanization of frontier forests. Although enforcement of hunting laws and promotion of alternative sources of protein may help curb the pressure on wildlife, the best strategy for biodiversity conservation may be to keep saw mills and the towns that develop around them out of forests.  相似文献   
62.
Abstract:  With about half the world's human population and booming economies, Asia faces numerous challenges to its biodiversity. The Asia Section of the Society for Conservation Biology has identified some key policy issues in which significant progress can be made. These include developing new sources of funding for forest conservation; identifying potential impacts of energy alternatives on the conservation of biodiversity; curbing the trade in endangered species of plants and animals; a special focus on the conservation of mountain biodiversity; enhancing relevant research; ensuring that conservation biology contributes to major international conventions and funding mechanisms; using conservation biology to build a better understanding of zoonotic diseases; more effectively addressing human–animal conflicts; enhancing community-based conservation; and using conservation biology to help address the pervasive water-deficit problems in much of Asia. These challenges can be met through improved regional cooperation among the relevant stakeholders .  相似文献   
63.
Abstract:  We reviewed research on wildlife overpasses in the context of their genetic effectiveness to provide connectivity between population patches that have been isolated by road construction. The potential ecological consequences of such habitat fragmentation include reduction of gene flow between subpopulations and hence an increase in genetic differentiation and a decrease in genetic diversity. Among the solutions to provide connectivity between patches isolated by roads, wildlife overpasses are one of the most expensive alternatives. Despite the high costs associated with their construction, most of the studies assessing their use by wildlife remain observational, reporting evidence for passage use but few data on the number of individual crossings. Moreover, the use itself of wildlife overpasses does not appear sufficient to assess their effectiveness from a genetic viewpoint because a minimum number of individuals is required to assure gene flow between population patches and because the spatiotemporal dimension of individual movements and demographic parameters of subpopulations must be considered. So far, there is no evidence that wildlife overpasses do or do not efficiently address genetic issues. This lack of data is probably due to the fact that few mitigation efforts have implemented monitoring programs that incorporate sufficient experimental designs into pre- and postconstruction evaluation. To assess the genetic effectiveness of wildlife overpasses, long-term monitoring programs, including fieldwork and genetic analyses, are needed.  相似文献   
64.
Understanding how the relationships between large carnivores and humans have evolved and have been managed through centuries can provide relevant insights for wildlife conservation. The management history of many large carnivores has followed a similar pattern, from game reserved for nobility, to persecuted pests, to conservation targets. We reconstructed the history of brown bear (Ursus arctos) management in Bia?owie?a Forest (Poland and Belarus) based on a detailed survey of historical literature and Russian archives. From the end of the Middle Ages to the end of 18th century, the brown bear was considered “animalia superiora” (i.e., game exclusively reserved for nobility and protected by law). Bears, also a source of public entertainment, were not regarded as a threat. Effective measures to prevent damages to traditional forest beekeeping were already in practice. In the beginning of 19th century, new game‐management approaches allowed most forest officials to hunt bears, which became the primary target of hunters due to their valuable pelt. This, together with an effective anticarnivore policy enhanced by bounties, led to bear extirpation in 1879. Different approaches to scientific game management appeared (planned extermination of predators and hunting levels that would maintain stable populations), as did the first initiatives to protect bears from cruel treatment in captivity. Bear reintroduction in Bia?owie?a Forest began in 1937 and represented the world's first reintroduction of a large carnivore motivated by conservation goals. The outbreak of World War II spoiled what might have been a successful project; reproduction in the wild was documented for 8 years and bear presence for 13. Soft release of cubs born in captivity inside the forest but freely roaming with minimal human contact proved successful. Release of captive human‐habituated bears, feeding of these bears, and a lack of involvement of local communities were weaknesses of the project. Large carnivores are key components of ecosystem‐function restoration, and site‐specific histories provide important lessons in how to preserve them for the future.  相似文献   
65.
66.
Overharvesting is one of the greatest threats to species survival. Farming overharvested species is a conservation strategy that can meet growing market demand and conserve wild populations of the target species. This strategy is compatible with the international community's desire to uphold the right of local communities to use biological resources to support their livelihoods. However, studies investigating whether farming can alleviate poaching pressure have focused almost exclusively on animals. To address the shortfall in plant-focused studies, we compiled information on commercial cultivation of threatened plants to assess its conservation benefits. Because China's rising middle class has rapidly intensified demand for wildlife products, we searched the scientific literature published in Chinese (China National Knowledge Infrastructure and Baidu) and in English. We found 32 reports that contained data on 193 internationally or nationally threatened plant species that were under commercial cultivation. These reports showed that cultivations of 82% of the 193 species were sustained by collecting whole plants from the wild periodically or continuously. Although based on a small sample size, species that were maintained in cultivation only through artificial propagation or seeds collected in the wild were likely associated with a reported reduction in wild harvesting of whole plants. Even so, results of correlation analyses suggested that production system, scale, and when a species began being cultivated had little effect on conservation status of the species, either globally or in China. However, species brought into cultivation relatively recently and on a smaller scale were more likely to have undergone a reduction in collecting pressure. Farming of nonmedicinal plants was most problematic for species conservation because wild plants were laundered (i.e., sold as cultivated plants). For effective conservation, policy to guide cultivation operations based on the target species’ biological characteristics, cultural significance, market demand, and conservation status is needed.  相似文献   
67.
The trade in wild animals involves one‐third of the world's bird species and thousands of other vertebrate species. Although a few species are imperiled as a result of the wildlife trade, the lack of field studies makes it difficult to gauge how serious a threat it is to biodiversity. We used data on changes in bird abundances across space and time and information from trapper interviews to evaluate the effects of trapping wild birds for the pet trade in Sumatra, Indonesia. To analyze changes in bird abundance over time, we used data gathered over 14 years of repeated bird surveys in a 900‐ha forest in southern Sumatra. In northern Sumatra, we surveyed birds along a gradient of trapping accessibility, from the edge of roads to 5 km into the forest interior. We interviewed 49 bird trappers in northern Sumatra to learn which species they targeted and how far they went into the forest to trap. We used prices from Sumatran bird markets as a proxy for demand and, therefore, trapping pressure. Market price was a significant predictor of species declines over time in southern Sumatra (e.g., given a market price increase of approximately $50, the log change in abundance per year decreased by 0.06 on average). This result indicates a link between the market‐based pet trade and community‐wide species declines. In northern Sumatra, price and change in abundance were not related to remoteness (distance from the nearest road). However, based on our field surveys, high‐value species were rare or absent across this region. The median maximum distance trappers went into the forest each day was 5.0 km. This suggests that trapping has depleted bird populations across our remoteness gradient. We found that less than half of Sumatra's remaining forests are >5 km from a major road. Our results suggest that trapping for the pet trade threatens birds in Sumatra. Given the popularity of pet birds across Southeast Asia, additional studies are urgently needed to determine the extent and magnitude of the threat posed by the pet trade.  相似文献   
68.
Persecution and overexploitation by humans are major causes of species extinctions. Rare species, often confined to small geographic ranges, are usually at highest risk, whereas extinctions of superabundant species with very large ranges are rare. The Yellow‐breasted Bunting (Emberiza aureola) used to be one of the most abundant songbirds of the Palearctic, with a very large breeding range stretching from Scandinavia to the Russian Far East. Anecdotal information about rapid population declines across the range caused concern about unsustainable trapping along the species’ migration routes. We conducted a literature review and used long‐term monitoring data from across the species’ range to model population trend and geographical patterns of extinction. The population declined by 84.3–94.7% between 1980 and 2013, and the species’ range contracted by 5000 km. Quantitative evidence from police raids suggested rampant illegal trapping of the species along its East Asian flyway in China. A population model simulating an initial harvest level of 2% of the population, and an annual increase of 0.2% during the monitoring period produced a population trajectory that matched the observed decline. We suggest that trapping strongly contributed to the decline because the consumption of Yellow‐breasted Bunting and other songbirds has increased as a result of economic growth and prosperity in East Asia. The magnitude and speed of the decline is unprecedented among birds with a comparable range size, with the exception of the Passenger Pigeon (Ectopistes migratorius), which went extinct in 1914 due to industrial‐scale hunting. Our results demonstrate the urgent need for an improved monitoring of common and widespread species’ populations, and consumption levels throughout East Asia.  相似文献   
69.
Many current wildlife conservation efforts in Africa focus on providing local communities with economic incentives to utilize wildlife as a form of land use in order to achieve the twin goals of ecological preservation as well as sustainable human economic development. Tanzanian Maasailand is home to some of the greatest concentrations of large mammals remaining outside National Parks and reserves, as well as a uniquely traditional human culture in the form of the Maasai themselves. Both are increasingly threatened by a variety of factors; poaching and habitat loss for wildlife, and the increasing marginalization of their pastoralist economy with regards to the Maasai. The fundamental cause of declining wildlife populations and biodiversity loss is that the Maasai have little economic or social interest in wildlife due to centralized management and financial benefits which are directed primarily to the Tanzanian state. Maasai pastoralism is highly compatible with wildlife, and the potential for the local communities to sustainably manage and benefit from this resource is promising. However, implementation of effective community-based natural resource management in the area faces political, cultural, and economic obstacles which will be critical in determining the outcomes of both conservation and community development efforts in Maasailand.  相似文献   
70.
ABSTRACT: The Yellowstone River historically has produced an ample supply of high quality water which is widely used for irrigation, municipal and industrial purposes, recreation, and fish and wildlife. Recently, energy companies have attempted to obtain water rights in the Yellowstone basin for energy conversion facilities in coal-rich southeastern Montana. Existing users fear that energy diversions will impair their rights, preclude expansion of present beneficial users, degrade water quality, and adversely effect fish and aquatic life. In response to these concerns, the Montana Legislature enacted several laws to regulate water appropriations in the Yellowstone River basin, including means by which state and federal agencies could apply for reservations of water for future beneficial uses. Thereafter, both the Montana Fish and Game Commission and the State Water Quality Bureau formally requested relatively large instream flows to protect fish and wildlife and to maintain water quality. This paper describes Montana's experience through December of 1977 with the administration of water in the Yellowstone basin under these laws; emphasis is placed on the major requests for instream flows. The final resolution of the reservation applications, and the related ramifications, will be discussed in a future paper.  相似文献   
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