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41.
Abstract: The international wildlife trade is a principal cause of biodiversity loss, involving hundreds of millions of plants and animals each year, yet wildlife trade records are notoriously unreliable. We assessed the precision of wildlife trade reports for the United States, the world's largest consumer of endangered wildlife, by comparing data from the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) with U.S. Customs data. For both U.S. imports and exports, CITES and Customs reported substantially different trade volumes for all taxa in all years. Discrepancies ranged from a CITES-reported volume 376% greater than that reported by Customs (live coral imports, 2000) to a Customs' report 5202% greater than CITES (conch exports, 2000). These widely divergent data suggest widespread inaccuracies that may distort the perceived risk of targeted wildlife exploitation, leading to misallocation of management resources and less effective conservation strategies. Conservation scientists and practitioners should reexamine assumptions regarding the significance of the international wildlife trade. 相似文献
42.
JENNIFER L. LAVERS MARK G. R. MILLER MICHAEL J. CARTER GEORGE SWANN ROHAN H. CLARKE 《Conservation biology》2014,28(6):1699-1709
Understanding spatial and temporal variability in the distribution of species is fundamental to the conservation of marine and terrestrial ecosystems. To support strategic decision making aimed at sustainable management of the oceans, such as the establishment of protected areas for marine wildlife, we identified areas predicted to support multispecies seabird aggregations in the Timor Sea. We developed species distribution models for 21 seabird species based on at‐sea survey observations from 2000–2013 and oceanographic variables (e.g., bathymetry). We applied 4 statistical modeling techniques and combined the results into an ensemble model with robust performance. The ensemble model predicted the probability of seabird occurrence in areas where few or no surveys had been conducted and demonstrated 3 areas of high seabird richness that varied little between seasons. These were located within 150 km of Adele Island, Ashmore Reef, and the Lacepede Islands, 3 of the largest aggregations of breeding seabirds in Australia. Although these breeding islands were foci for high species richness, model performance was greatest for 3 nonbreeding migratory species that would have been overlooked had regional monitoring been restricted to islands. Our results indicate many seabird hotspots in the Timor Sea occur outside existing reserves (e.g., Ashmore Reef Marine Reserve), where shipping, fisheries, and offshore development likely pose a threat to resident and migratory populations. Our results highlight the need to expand marine spatial planning efforts to ensure biodiversity assets are appropriately represented in marine reserves. Correspondingly, our results support the designation of at least 4 new important bird areas, for example, surrounding Adele Island and Ashmore Reef. Pronostico de la Distribución Espacial de una Comunidad de Aves Marinas para Identificar Áreas Prioritarias de Conservación en el Mar de Timor 相似文献
43.
NYAMSUREN BATSAIKHAN BAYARBAATAR BUUVEIBAATAR BAZAAR CHIMED OIDOV ENKHTUYA DAVAA GALBRAKH OYUNSAIKHAN GANBAATAR BADAMJAV LKHAGVASUREN DEJID NANDINTSETSEG JOEL BERGER JUSTIN M. CALABRESE ANN E. EDWARDS WILLIAM F. FAGAN TODD K. FULLER MICHAEL HEINER TAKEHIKO Y. ITO PETRA KACZENSKY PETER LEIMGRUBER ANNA LUSHCHEKINA E.J. MILNER‐GULLAND THOMAS MUELLER MARTYN G. MURRAY KIRK A. OLSON RICHARD READING GEORGE B. SCHALLER ANNAGRET STUBBE MICHAEL STUBBE CHRIS WALZER HENRIK VON WEHRDEN TONY WHITTEN 《Conservation biology》2014,28(6):1736-1739
44.
On the basis of representative data collected in 1991 as part of the German General Social Survey (ALLBUS) Baseline Study in East and West Germany an answer is sought to the question whether East Germans differ from West Germans with respect to work values. Work values are classified into existence, growth and relatedness (ERG) categories and, at the same time, into performance-dependent and performance-independent ones. As from previous studies it is known that East Germans put more emphasis on existence and on relatedness values than West Germans, while growth values are weighted identically in both parts of Germany, the present paper concentrates on the structural aspect. Employing multidimensional scaling (MDS) it can be demonstrated that the structures of work values are highly similar in East and West Germany: both samples verify the ERG- and the performance-dependency facet in the same way, i.e. by exhibiting radex patterns. Moreover, the item correlations are all positive in both samples, as predicted by a new theory of directed behavior. Finally, after subtracting the value scores of each individual from the individual's mean score, the item correlations in both East and West Germany are largely compatible with predictions derived from Alderfer's theory of motivation. Thus, widespread assumptions about fundamental differences in the work values of East and West Germans prove false in many ways. 相似文献
45.
MHC and Captive Breeding: A Rebuttal 总被引:1,自引:0,他引:1
46.
47.
MICHAEL J. FORD§ JEFFREY J. HARD BRANT BOELTS† ERIC LaHOOD JASON MILLER 《Conservation biology》2008,22(3):783-794
Abstract: Captive breeding is a commonly used strategy for species conservation. One risk of captive breeding is domestication selection—selection for traits that are advantageous in captivity but deleterious in the wild. Domestication selection is of particular concern for species that are bred in captivity for many generations and that have a high potential to interbreed with wild populations. Domestication is understood conceptually at a broad level, but relatively little is known about how natural selection differs empirically between wild and captive environments. We used genetic parentage analysis to measure natural selection on time of migration, weight, and morphology for a coho salmon ( Oncorhynchus kisutch ) population that was subdivided into captive and natural components. Our goal was to determine whether natural selection acting on the traits we measured differed significantly between the captive and natural environments. For males, larger individuals were favored in both the captive and natural environments in all years of the study, indicating that selection on these traits in captivity was similar to that in the wild. For females, selection on weight was significantly stronger in the natural environment than in the captive environment in 1 year and similar in the 2 environments in 2 other years. In both environments, there was evidence of selection for later time of return for both males and females. Selection on measured traits other than weight and run timing was relatively weak. Our results are a concrete example of how estimates of natural selection during captivity can be used to evaluate this common risk of captive breeding programs. 相似文献
48.
MORENA MILLS SAM NICOL JESSIE A. WELLS JOSÉ J. LAHOZ‐MONFORT BRENDAN WINTLE MICHAEL BODE MARTIN WARDROP TERRY WALSHE WILLIAM J. M. PROBERT MICHAEL C. RUNGE HUGH P. POSSINGHAM EVE MCDONALD MADDEN 《Conservation biology》2014,28(3):646-653
Policy documents advocate that managers should keep their options open while planning to protect coastal ecosystems from climate‐change impacts. However, the actual costs and benefits of maintaining flexibility remain largely unexplored, and alternative approaches for decision making under uncertainty may lead to better joint outcomes for conservation and other societal goals. For example, keeping options open for coastal ecosystems incurs opportunity costs for developers. We devised a decision framework that integrates these costs and benefits with probabilistic forecasts for the extent of sea‐level rise to find a balance between coastal ecosystem protection and moderate coastal development. Here, we suggest that instead of keeping their options open managers should incorporate uncertain sea‐level rise predictions into a decision‐making framework that evaluates the benefits and costs of conservation and development. In our example, based on plausible scenarios for sea‐level rise and assuming a risk‐neutral decision maker, we found that substantial development could be accommodated with negligible loss of environmental assets. Characterization of the Pareto efficiency of conservation and development outcomes provides valuable insight into the intensity of trade‐offs between development and conservation. However, additional work is required to improve understanding of the consequences of alternative spatial plans and the value judgments and risk preferences of decision makers and stakeholders. Minimizando el Costo de Mantener Opciones Abiertas para la Conservación en un Clima Cambiante 相似文献
49.
DAVID A. KEITH MICHAEL MAHONY HARRY HINES JANE ELITH TRACEY J. REGAN JOHN B. BAUMGARTNER DAVID HUNTER GEOFFREY W. HEARD NICOLA J. MITCHELL KIRSTEN M. PARRIS TRENT PENMAN BEN SCHEELE CHRISTOPHER C. SIMPSON REID TINGLEY CHRISTOPHER R. TRACY MATT WEST H. RESIT AKÇAKAYA 《Conservation biology》2014,28(3):810-819
Anthropogenic climate change is a key threat to global biodiversity. To inform strategic actions aimed at conserving biodiversity as climate changes, conservation planners need early warning of the risks faced by different species. The IUCN Red List criteria for threatened species are widely acknowledged as useful risk assessment tools for informing conservation under constraints imposed by limited data. However, doubts have been expressed about the ability of the criteria to detect risks imposed by potentially slow‐acting threats such as climate change, particularly because criteria addressing rates of population decline are assessed over time scales as short as 10 years. We used spatially explicit stochastic population models and dynamic species distribution models projected to future climates to determine how long before extinction a species would become eligible for listing as threatened based on the IUCN Red List criteria. We focused on a short‐lived frog species (Assa darlingtoni) chosen specifically to represent potential weaknesses in the criteria to allow detailed consideration of the analytical issues and to develop an approach for wider application. The criteria were more sensitive to climate change than previously anticipated; lead times between initial listing in a threatened category and predicted extinction varied from 40 to 80 years, depending on data availability. We attributed this sensitivity primarily to the ensemble properties of the criteria that assess contrasting symptoms of extinction risk. Nevertheless, we recommend the robustness of the criteria warrants further investigation across species with contrasting life histories and patterns of decline. The adequacy of these lead times for early warning depends on practicalities of environmental policy and management, bureaucratic or political inertia, and the anticipated species response times to management actions. Detección del Riesgo de Extinción a partir del Cambio Climático por medio del Criterio de la Lista Roja de la UICNKeith et al. 相似文献
50.
JAMES N. SANCHIRICO MICHAEL R. SPRINGBORN MARK W. SCHWARTZ ANGELA N. DOERR 《Conservation biology》2014,28(2):361-371
Despite decades of discussion and implementation, conservation monitoring remains a challenge. Many current solutions in the literature focus on improving the science or making more structured decisions. These insights are important but incomplete in accounting for the politics and economics of the conservation decisions informed by monitoring. Our novel depiction of the monitoring enterprise unifies insights from multiple disciplines (conservation, operations research, economics, and policy) and highlights many underappreciated factors that affect the expected benefits of monitoring. For example, there must be a strong link between the specific needs of decision makers and information gathering. Furthermore, the involvement of stakeholders other than scientists and research managers means that new information may not be interpreted and acted upon as expected. While answering calls for sharply delineated objectives will clearly add focus to monitoring efforts, for practical reasons, high‐level goals may purposefully be left vague, to facilitate other necessary steps in the policy process. We use the expanded depiction of the monitoring process to highlight problems of cooperation and conflict. We critique calls to invest in monitoring for the greater good by arguing that incentives are typically lacking. Although the benefits of learning accrued within a project (e.g., improving management) provide incentives for investing in some monitoring, it is unrealistic, in general, to expect managers to add potentially costly measures to generate shared benefits. In the traditional linear model of the role of science in policy decisions, monitoring reduces uncertainty and decision makers are rational, unbiased consumers of the science. However, conservation actions increasingly involve social conflict. Drawing insights from political science, we argue that in high‐conflict situations, it is necessary to address the conflict prior to monitoring. Las Inversiones y el Proceso de Políticas en el Monitoreo de la Conservación Sanchirico et al. 相似文献