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1.
Understanding the Diversity of Public Interests in Wildlife Conservation   总被引:3,自引:0,他引:3  
Abstract:  North American state wildlife agencies are increasingly faced with the challenge of effectively representing a diverse public. With increasing social conflict over wildlife issues, the future of wildlife conservation hinges on preparedness of the profession to respond to this challenge. In the interest of finding ways to improve response, 19 agencies in the western U.S. joined forces to initiate an investigation that would provide a better understanding of the diversity of wildlife-related interests in the region. Specific objectives, accomplished through use of a mail survey administered in 2004, were to categorize people on the basis of their value orientations toward wildlife and explore how different groups were distributed across states and to examine differences on sociodemographic characteristics and attitudes toward wildlife-related topics among groups. The focus was on two orientations: domination (view of wildlife that prioritizes human well-being over wildlife and treats wildlife in utilitarian terms); and mutualism (view of wildlife as capable of relationships of trust with humans and defined by a desire for companionship with wildlife). Four types of people were identified on the basis of these orientations. Types differed in their geographic distribution and wildlife-related attitudes and behaviors, revealing how value orientations can form the foundation for conflict on wildlife issues. Our characterizations of stakeholder groups offer a framework that can be applied over time and across geographic scales to improve conservation planning efforts and inform broader thinking about the social aspects of wildlife conservation .  相似文献   
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Abstract: Despite the growing interest in conservation approaches that include payments for environmental services (PES), few evaluations of the influence of such interventions on behaviors of individuals have been conducted. We used self‐reported changes in six legal and illegal forest‐use behaviors to investigate the way in which a PES for biodiversity conservation intervention in Menabe, Madagascar, influenced behavior. Individuals (n =864) from eight intervention communities and five control communities answered questions on their forest‐use behaviors before and after the intervention began, as well as on their reasons for changing and their attitudes to various institutions. The payments had little impact on individuals’ reported decisions to change behaviors, but it had a strong impact on individuals’ attitudes. Payments appeared to legitimize monitoring of behaviors by the implementing nongovernmental organization (NGO), but did not act as a behavioral driver in their own right. Although there were no clear differences between changes in behaviors in the intervention and control communities, the intervention did influence motivations for change. Fear of local forest associations and the implementing NGO were strong motivators for changing behavior in communities with the PES intervention, whereas fear of the national government was the main reason given for change in control communities. Behavioral changes were most stable where fear of local organizations motivated the change. Our results highlight the interactions between different incentives people face when making behavioral decisions and the importance of considering the full range of incentives when designing community‐based PES interventions.  相似文献   
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Abstract: The U.S. Endangered Species Act (ESA) defines an endangered species as one “at risk of extinction throughout all or a significant portion of its range.” The prevailing interpretation of this phrase, which focuses exclusively on the overall viability of listed species without regard to their geographic distribution, has led to development of listing and recovery criteria with fundamental conceptual, legal, and practical shortcomings. The ESA's concept of endangerment is broader than the biological concept of extinction risk in that the “esthetic, ecological, educational, historical, recreational, and scientific” values provided by species are not necessarily furthered by a species mere existence, but rather by a species presence across much of its former range. The concept of “significant portion of range” thus implies an additional geographic component to recovery that may enhance viability, but also offers independent benefits that Congress intended the act to achieve. Although the ESA differs from other major endangered‐species protection laws because it acknowledges the distinct contribution of geography to recovery, it resembles the “representation, resiliency, and redundancy” conservation‐planning framework commonly referenced in recovery plans. To address representation, listing and recovery standards should consider not only what proportion of its former range a species inhabits, but the types of habitats a species occupies and the ecological role it plays there. Recovery planning for formerly widely distributed species (e.g., the gray wolf [Canis lupus]) exemplifies how the geographic component implicit in the ESA's definition of endangerment should be considered in determining recovery goals through identification of ecologically significant types or niche variation within the extent of listed species, subspecies, or “distinct population segments.” By linking listing and recovery standards to niche and ecosystem concepts, the concept of ecologically significant type offers a scientific framework that promotes more coherent dialogue concerning the societal decisions surrounding recovery of endangered species.  相似文献   
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Although the concept of connectivity is decades old, it remains poorly understood and defined, and some argue that habitat quality and area should take precedence in conservation planning instead. However, fragmented landscapes are often characterized by linear features that are inherently connected, such as streams and hedgerows. For these, both representation and connectivity targets may be met with little effect on the cost, area, or quality of the reserve network. We assessed how connectivity approaches affect planning outcomes for linear habitat networks by using the stock‐route network of Australia as a case study. With the objective of representing vegetation communities across the network at a minimal cost, we ran scenarios with a range of representation targets (10%, 30%, 50%, and 70%) and used 3 approaches to account for connectivity (boundary length modifier, Euclidean distance, and landscape‐value [LV]). We found that decisions regarding the target and connectivity approach used affected the spatial allocation of reserve systems. At targets ≥50%, networks designed with the Euclidean distance and LV approaches consisted of a greater number of small reserves. Hence, by maximizing both representation and connectivity, these networks compromised on larger contiguous areas. However, targets this high are rarely used in real‐world conservation planning. Approaches for incorporating connectivity into the planning of linear reserve networks that account for both the spatial arrangement of reserves and the characteristics of the intervening matrix highlight important sections that link the landscape and that may otherwise be overlooked. El Efecto de la Planeación para la Conectividad en Redes de Reservas Lineales  相似文献   
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Abstract: Unintended effects of recreational activities in protected areas are of growing concern. We used an adaptive‐management framework to develop guidelines for optimally managing hiking activities to maintain desired levels of territory occupancy and reproductive success of Golden Eagles (Aquila chrysaetos) in Denali National Park (Alaska, U.S.A.). The management decision was to restrict human access (hikers) to particular nesting territories to reduce disturbance. The management objective was to minimize restrictions on hikers while maintaining reproductive performance of eagles above some specified level. We based our decision analysis on predictive models of site occupancy of eagles developed using a combination of expert opinion and data collected from 93 eagle territories over 20 years. The best predictive model showed that restricting human access to eagle territories had little effect on occupancy dynamics. However, when considering important sources of uncertainty in the models, including environmental stochasticity, imperfect detection of hares on which eagles prey, and model uncertainty, restricting access of territories to hikers improved eagle reproduction substantially. An adaptive management framework such as ours may help reduce uncertainty of the effects of hiking activities on Golden Eagles.  相似文献   
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Wildlife diseases pose an increasing threat to biodiversity and are a major management challenge. A striking example of this threat is the emergence of chytridiomycosis. Despite diagnosis of chytridiomycosis as an important driver of global amphibian declines 15 years ago, researchers have yet to devise effective large‐scale management responses other than biosecurity measures to mitigate disease spread and the establishment of disease‐free captive assurance colonies prior to or during disease outbreaks. We examined the development of management actions that can be implemented after an epidemic in surviving populations. We developed a conceptual framework with clear interventions to guide experimental management and applied research so that further extinctions of amphibian species threatened by chytridiomycosis might be prevented. Within our framework, there are 2 management approaches: reducing Batrachochytrium dendrobatidis (the fungus that causes chytridiomycosis) in the environment or on amphibians and increasing the capacity of populations to persist despite increased mortality from disease. The latter approach emphasizes that mitigation does not necessarily need to focus on reducing disease‐associated mortality. We propose promising management actions that can be implemented and tested based on current knowledge and that include habitat manipulation, antifungal treatments, animal translocation, bioaugmentation, head starting, and selection for resistance. Case studies where these strategies are being implemented will demonstrate their potential to save critically endangered species. Intervenciones para Reducir el Riesgo de Extinción en Anfibios Amenazados por la Quitridiomicosis  相似文献   
8.
Abstract: Conservation biologists often face the trade‐off that increasing connectivity in fragmented landscapes to reduce extinction risk of native species can foster invasion by non‐native species that enter via the corridors created, which can then increase extinction risk. This dilemma is acute for stream fishes, especially native salmonids, because their populations are frequently relegated to fragments of headwater habitat threatened by invasion from downstream by 3 cosmopolitan non‐native salmonids. Managers often block these upstream invasions with movement barriers, but isolation of native salmonids in small headwater streams can increase the threat of local extinction. We propose a conceptual framework to address this worldwide problem that focuses on 4 main questions. First, are populations of conservation value present (considering evolutionary legacies, ecological functions, and socioeconomic benefits as distinct values)? Second, are populations vulnerable to invasion and displacement by non‐native salmonids? Third, would these populations be threatened with local extinction if isolated with barriers? And, fourth, how should management be prioritized among multiple populations? We also developed a conceptual model of the joint trade‐off of invasion and isolation threats that considers the opportunities for managers to make strategic decisions. We illustrated use of this framework in an analysis of the invasion‐isolation trade‐off for native cutthroat trout (Oncorhynchus clarkii) in 2 contrasting basins in western North America where invasion and isolation are either present and strong or farther away and apparently weak. These cases demonstrate that decisions to install or remove barriers to conserve native salmonids are often complex and depend on conservation values, environmental context (which influences the threat of invasion and isolation), and additional socioeconomic factors. Explicit analysis with tools such as those we propose can help managers make sound decisions in such complex circumstances.  相似文献   
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Abstract: The importance of topography in evaluation of insect conservation is discussed with reference to grasshoppers in the Natal Drakensberg Mountains, South Africa For these insects, the hilltops act as thermal refugia from winter cold air drainage. Additionally, the increased insolation on the eastern and northern sides of the hilltops, compared with the western and southern sides, attracts the grasshoppers. Crevices in the hill summits provide further microrefugia Burning reduces grasshopper numbers by half and although many species are adapted to burn conditions, the reduced grass cover accentuates the thermal influences. Other animals, and plants, also selectively inhabit these hilltops, making them highly significant conservation refugia in a matrix of thermally inhospitable land. Evaluations for biological conservation should take note of the strong influence that land forms may have on plant and animal local distributions.  相似文献   
10.
Abstract:  In the boreal forests of Fennoscandia, over 99% of forest area has been altered by forestry practices, which has created forest with age structures and stand characteristics that differ from primary forest stands. Although many researchers have investigated how forestry affects species abundance, few have assessed how forestry practices affect fitness correlates of species living in altered habitats, and this has negatively affected management efforts. We experimentally addressed the effect of standard forestry practices on fitness correlates of an open-nesting, long-lived bird species typical to boreal forests of Eurasia, the Siberian Jay ( Perisoreus infaustus ). We used a before-after comparison of reproductive data on the level of territories and found that standard forestry practices had a strong negative effect on the breeding success of jays. Both partial thinning of territories and partial clearcutting of territories reduced future breeding success by a factor of 0.35. Forestry practices reduced territory occupancy. Thus, over the 15 years of the study, productivity of the affected population declined over 50% as a result of territory abandonment and reduced breeding success. Results of previous studies on Siberian Jays suggest that the strong effect of forest thinning on fitness is explained by the fact that most common predators of nests and adults are visually oriented and thus thinning makes prey and nests more visible to predators. The consequences of thinning we observed are likely to apply to a wide range of species that rely on understory to provide visual protection from predators. Thus, our results are important for the development of effective conservation management protocols and for the refinement of thinning practices.  相似文献   
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