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41.
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
42.
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
43.
Abstract: Marine protected areas (MPAs) are a popular conservation strategy, but their impacts on human welfare are poorly understood. To inform future research and policy decisions, we reviewed the scientific literature to assess MPA impacts on five indicators of human welfare: food security, resource rights, employment, community organization, and income. Following MPA establishment, food security generally remained stable or increased in older and smaller MPAs. The ability of most fishing groups to govern MPA resources changed. Increased resource rights were positively correlated with MPA zoning and compliance with MPA regulations. Small sample sizes precluded statistical tests of the impacts of MPAs on employment, community organization, and income. Our results demonstrate that MPAs shape the social well‐being and political power of fishing communities; impacts (positive and negative) vary within and among social groups; and social impacts are correlated with some—but not all—commonly hypothesized explanatory factors. Accordingly, MPAs may represent a viable strategy for enhancing food security and empowering local communities, but current practices negatively affect at least a minority of fishers. To inform policy making, further research must better document and explain variation in the positive and negative social impacts of MPAs. 相似文献
44.
DANIEL SPRING JIRI BAUM RALPH MAC NALLY MICHAEL MACKENZIE A. SANCHEZ‐AZOFEIFA JAMES R. THOMSON 《Conservation biology》2010,24(3):691-700
Abstract: Habitat connectivity is required at large spatial scales to facilitate movement of biota in response to climatic changes and to maintain viable populations of wide‐ranging species. Nevertheless, it may require decades to acquire habitat linkages at such scales, and areas that could provide linkages are often developed before they can be reserved. Reserve scheduling methods usually consider only current threats, but threats change over time as development spreads and reaches presently secure areas. We investigated the importance of considering future threats when implementing projects to maintain habitat connectivity at a regional scale. To do so, we compared forward‐looking scheduling strategies with strategies that consider only current threats. The strategies were applied to a Costa Rican case study, where many reserves face imminent isolation and other reserves will probably become isolated in the more distant future. We evaluated strategies in terms of two landscape‐scale connectivity metrics, a pure connectivity metric and a metric of connected habitat diversity. Those strategies that considered only current threats were unreliable because they often failed to complete planned habitat linkage projects. The most reliable and effective strategies considered the future spread of development and its impact on the likelihood of completing planned habitat linkage projects. Our analyses highlight the critical need to consider future threats when building connected reserve networks over time. 相似文献
45.
Abstract: Open access (OA) publishing, whereby authors, their institutions, or their granting bodies pay or provide a repository through which peer‐reviewed work is available online for free, is championed as a model to increase the number of citations per paper and disseminate results widely, especially to researchers in developing countries. We compared the number of citations of OA and non‐OA papers in six journals and four books published since 2000 to test whether OA increases number of citations overall and increases citations made by authors in developing countries. After controlling for type of paper (e.g., review or research paper), length of paper, authors’ citation profiles, number of authors per paper, and whether the author or the publisher released the paper in OA, OA had no statistically significant influence on the overall number of citations per journal paper. Journal papers were cited more frequently if the authors had published highly cited papers previously, were members of large teams of authors, or published relatively long papers, but papers were not cited more frequently if they were published in an OA source. Nevertheless, author‐archived OA book chapters accrued up to eight times more citations than chapters in the same book that were not available through OA, perhaps because there is no online abstracting service for book chapters. There was also little evidence that journal papers or book chapters published in OA received more citations from authors in developing countries relative to those journal papers or book chapters not published in OA. For scholarly publications in conservation biology, only book chapters had an OA citation advantage, and OA did not increase the number of citations papers or chapters received from authors in developing countries. 相似文献
46.
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
47.
MHC and Captive Breeding: A Rebuttal 总被引:1,自引:0,他引:1
48.
49.
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
50.
This paper explores the positive aspects of collaboration in natural resources. Its purpose was to investigate participants'
overall attitudes about keys to successful collaboration. The sample for the study consisted of 671 participants involved
in 30 collaborative initiatives (CI) with the Forest Service. Using a mailed questionnaire, this study profiled the collaborative
initiatives investigating purpose, problems addressed, groups involved, and years in existence. Respondents were queried on
their overall perspectives on keys to successful collaboration. A total of more than 300 comments was collected from respondents
and six categories emerged: development, information exchange, organizational support, personal communication, relationships/team
building, and accomplishments. Continued research will need to explore the short- and long-term impacts of collaboration in
natural resources. 相似文献