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1.
Regardless of many legal restrictions, the keeping of and trade in reptiles as pets has been increasing in Brazil over the last few years. We present an analysis of the trade and use of reptiles as pets in Brazil and discuss the implications. Data were obtained through semi-structured questionnaires given to 719 owners, who were contacted through reptile-owner groups on the social network Facebook. A total of 69 reptile species were reported as pets in Brazil, of which there were 39 snakes, 17 lizards, 12 chelonians and 1 species of crocodilian. Of the reported species, 46 are native to Brazil and 23 are exotic, including threatened species. Owners were distributed in at least 24 states, with a higher concentration in Southeast Brazil and the Federal District. Owners usually acquire animals through purchase, although prices vary and are high for some species, making reptile ownership more common among high-income individuals. Prices were affected by factors such as beauty, colour pattern, size, sex and even rarity. The keeping of reptiles as pets raises conservation concerns, as the practice directly impacts exploited populations and is a potential introduction pathway for invasive species, including exotic species that have already been recorded in natural habitats in Brazil. A thorough discussion, encompassing various stakeholders — namely, owners, traders and environmental authorities — is much needed, to address management strategies, and propose feasible solutions. Conservation and animal welfare NGOs should also be involved in this process.  相似文献   
2.
Understanding of the ecology of infected animals facilitates disease risk assessment and is also crucial for wildlife conservation. Relatively little is known about the spatial distribution of infected wild mammals in relation to environmental factors. In neighboring Mediterranean ecosystems 250 European brown hares (Lepus europaeus) were collected and examined with RT-PCR to detect European Brown Hare Syndrome Virus (EBHSV). Multivariate statistics and Geographical Information System (GIS) analysis were applied to estimate spatial patterns of biotic and abiotic factors and human activities as determinants of EBHSV positivity. Hare population abundance was estimated using faeces counts and belt drive censuses. The study showed that EBHSV infected hares had widespread distribution even in isolated areas. However, EBHSV infection prevalence was higher in areas with higher hare abundance, closer to paved road networks and at lower altitudes. The risk map revealed the potential distribution of EBHSV-infected hares. This study shows that host abundance and landscape influence the ecology of the disease, a finding that should be taken into account in future studies. The management of harvest and restocking of hares is also discussed for population conservation.  相似文献   
3.
Line transect counting of a wildlife population is considered a sampling from a planar marked point process, where the marks describe the detectability of the animals. Sampling properties of transect counts and a new density estimator are derived from a counting process, which is a shot-noise field induced by the marked point process. A general formula for the sampling variance of a transect is derived and applied to compare five common types of transects. Some stereological connections of transect sampling and density estimators are shown.  相似文献   
4.
In northcentral Namibia, Waterberg Plateau Park (WPP) is a protected area that acts as a refuge for rare and endangered species, while the farmlands surrounding the Park are managed for livestock production, but support populations of wildlife for game farming, trophy hunting, and conservation. During June–October 2006, camera-traps were set within and surrounding WPP to assess leopard (Panthera pardus) density (n = 19 camera stations and 946 camera-trap-nights). Fortuitously, photographic results (2,265 photos of identifiable mammal (n = 37) and bird (n = 25) species) allowed us to assess aspects of species diversity and differences among the Park, the farmland areas along the Waterberg Plateau escarpment, and the flatlands surrounding the escarpment. Species composition among the three areas was markedly different, and made sense with respect to differences in habitat and management features. Camera-trapping efforts, although intended for a narrow purpose, may also provide a rather robust record of differences in mammal and bird diversity in adjacent habitats and can be incorporated into long-term monitoring programs.  相似文献   
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6.
Lowland rainforests on Borneo are being degraded and lost at an alarming rate. Studies on mammals report species responding in various ways to habitat changes that occur in commercial forestry concessions. Here we draw together information on the relationship between the ecological, evolutionary, and biogeographic characteristics of selected Bornean non-volant mammals, and their response to timber harvesting and related impacts. Only a minority of species show markedly reduced densities after timber harvesting. Nonetheless there are many grounds for concern as various processes can, and often do, reduce the viability of wildlife populations. Our review of what we know, and of current understanding, helps predict mammalian dynamics and subsequent mammal-induced ecosystem changes in logged forests. We identify groups of mammal species that, although largely unstudied, are unlikely to tolerate the impacts associated with timber harvesting. On a positive note we find and suggest many relatively simple and low-cost ways in which concession management practices might be modified so as to improve the value of managed forests for wildlife conservation. Improving forest management can play a vital role in maintaining the rich biodiversity of Borneo’s tropical rain forests.  相似文献   
7.
Abstract: In a natural resource management setting, monitoring is a crucial component of an informed process for making decisions, and monitoring design should be driven by the decision context and associated uncertainties. Monitoring itself can play ≥3 roles. First, it is important for state-dependent decision-making, as when managers need to know the system state before deciding on the appropriate course of action during the ensuing management cycle. Second, monitoring is critical for evaluating the effectiveness of management actions relative to objectives. Third, in an adaptive management setting, monitoring provides the feedback loop for learning about the system; learning is sought not for its own sake but primarily to better achieve management objectives. In this case, monitoring should be designed to reduce the critical uncertainties in models of the managed system. The United States Geological Survey and United States Fish and Wildlife Service are conducting a large-scale management experiment on 23 National Wildlife Refuges across the Northeast and Midwest Regions. The primary management objective is to provide habitat for migratory waterbirds, particularly during migration, using water-level manipulations in managed wetlands. Key uncertainties are related to the potential trade-offs created by management for a specific waterbird guild (e.g., migratory shorebirds) and the response of waterbirds, plant communities, and invertebrates to specific experimental hydroperiods. We reviewed the monitoring program associated with this study, and the ways that specific observations fill ≥1 of the roles identified above. We used observations from our monitoring to improve state-dependent decisions to control undesired plants, to evaluate management performance relative to shallow-water habitat objectives, and to evaluate potential trade-offs between waterfowl and shorebird habitat management. With limited staff and budgets, management agencies need efficient monitoring programs that are used for decision-making, not comprehensive studies that elucidate all manner of ecological relationships.  相似文献   
8.
We assessed the effectiveness of national and international wildlife trade regulations in Asia by surveying four wildlife markets in Myanmar for bears and bear parts. Bears are protected in Myanmar and neighbouring countries, and are included in CITES Appendix I, precluding international trade. Three of the four wildlife markets were situated at the border with neighbouring countries (China and Thailand) whereas the fourth, situated in Myanmar’s interior, also catered to international markets. During seven checks (1999–2006) we recorded 1,200 bear parts, representing a minimum of 215 individual bears. Most items were from Asiatic black bears Ursus thibetanus but also sun bear Helarctos malayanus parts were offered for sale. There were significant temporal and spatial differences in what items were offered for sale. Prices were low (USD 4–40 per item) and the total monetary value of the items for sale was USD 6,500–9,500 (not including gall bladders). Carcasses, skulls, canines, paws, claws, whole skins, pieces of skin, gall bladders and derivates, were openly displayed, with vendors being frank about prices, origin, and potential buyers. Only in the interior were prices quoted in the local currency; at the other three markets currencies of the neighbouring countries were used. Legal (international) trade in bears or bear parts from Myanmar is virtually non-existent, and the observed trade in bear parts strongly indicates a serious lack of enforcement effort. International trade in bear parts from Myanmar is significant, and open, and we conclude that the enforcement of wildlife trade regulations, at least when they concerns bear species, have by and large failed.  相似文献   
9.
The private game industry has grown across Africa since the mid-20th century. While considerable research has documented wildlife production on commercial land in many eastern and southern African countries, few studies have focused specifically on the integration of livestock and game production in Namibia and Zambia. This paper reports a survey of 43 commercial conservancy members in Namibia and 23 game farmers in Zambia conducted between September 2004 and June 2005. The survey was based on inductive sampling theory and queried farmers on how they have integrated wildlife production into their management practices. Farmers in each country reported considerable integration of wildlife conservation and agricultural production. Namibian farmers reported substantial problems with bush encroachment, whereas none of their Zambian counterparts raised similar complaints. This paper describes the state of rangeland management on commercial farms in Namibia and Zambia and identifies important areas where further research can contribute to the enhancement of this conservation-production system.  相似文献   
10.
Traditional ecological knowledge (TEK) is a potential source of ecological information. Typically TEK has been documented at the species level, but habitat data would be equally valuable for conservation applications. We compared the TEK forest type classification of ribereños, the non-indigenous rural peasantry of Peruvian Amazonia, to a floristic classification produced using systematically collected botanical data. Indicator species analysis of pteridophytes in 300 plots detected two forest types on non-flooded tierra firme, each associated with distinct soil texture and fertility, and one forest type in areas subject to flooding. Nine TEK forest types were represented in the same set of plots. Each TEK forest type was consistently (>82%) associated with one of the three floristic classes and there were also clear parallels in the ecological characterizations of the forest types. Ribereños demonstrated clear preferences for certain forest types when selecting sites for slash-and-burn agriculture and hunting. Our results indicate that the non-tribal inhabitants of Amazonia possess valuable TEK that could be used in biodiversity inventories and wildlife management and conservation for characterizing primary rain forest habitats in Amazonia.  相似文献   
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