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Conservation Benefits of Temperate Marine Protected Areas: Variation among Fish Species 总被引:2,自引:0,他引:2
ROBERT E. BLYTH-SKYRME MICHEL J. KAISER§ JAN G. HIDDINK GARETH EDWARDS-JONES† PAUL J. B. HART‡ 《Conservation biology》2006,20(3):811-820
Abstract: Marine protected areas, and other fishery management systems that impart partial or total protection from fishing, are increasingly advocated as an essential management tool to ensure the sustainable use of marine resources. Beneficial effects for fish species are well documented for tropical and reef systems, but the effects of marine protected areas remain largely untested in temperate waters. We compared trends in sport-fishing catches of nine fish species in an area influenced by a large (500-km2 ) towed-fishing-gear restriction zone and in adjacent areas under conventional fishery management controls. Over the period 1973–2002 the mean reported weight of above-average-sized (trophy) fish of species with early age at maturity and limited home range was greatest within the area influenced by the fishing-gear restriction zone. The reported weight of trophy fish of species that mature early also declined less and more slowly over time within the area influenced by the fishing-gear restriction zone. Importantly, the mean reported weight of trophy fish of species that mature late and those that undertake extensive spatial movements declined at the same rate in all areas. Hence these species are likely to require protected areas >500 km2 for effective protection. Our results also indicated that fish species with a localized distribution or high site fidelity may require additional protection from sport fishing to prevent declines in the number or size of fish within the local population. 相似文献
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Extinction Debt of Protected Areas in Developing Landscapes 总被引:3,自引:1,他引:3
CARLOS CARROLL REED F. NOSS† PAUL C. PAQUET‡ NATHAN H. SCHUMAKER§ 《Conservation biology》2004,18(4):1110-1120
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Establishing IUCN Red List Criteria for Threatened Ecosystems 总被引:1,自引:0,他引:1
JON PAUL RODRÍGUEZ KATHRYN M. RODRÍGUEZ‐CLARK JONATHAN E. M. BAILLIE NEVILLE ASH JOHN BENSON TIMOTHY BOUCHER CLAIRE BROWN NEIL D. BURGESS BEN COLLEN MICHAEL JENNINGS DAVID A. KEITH EMILY NICHOLSON CARMEN REVENGA BELINDA REYERS TAMMY SMITH MARK SPALDING ANDREW TABER MATT WALPOLE IRENE ZAGER TARA ZAMIN 《Conservation biology》2011,25(1):21-29
Abstract: The potential for conservation of individual species has been greatly advanced by the International Union for Conservation of Nature's (IUCN) development of objective, repeatable, and transparent criteria for assessing extinction risk that explicitly separate risk assessment from priority setting. At the IV World Conservation Congress in 2008, the process began to develop and implement comparable global standards for ecosystems. A working group established by the IUCN has begun formulating a system of quantitative categories and criteria, analogous to those used for species, for assigning levels of threat to ecosystems at local, regional, and global levels. A final system will require definitions of ecosystems; quantification of ecosystem status; identification of the stages of degradation and loss of ecosystems; proxy measures of risk (criteria); classification thresholds for these criteria; and standardized methods for performing assessments. The system will need to reflect the degree and rate of change in an ecosystem's extent, composition, structure, and function, and have its conceptual roots in ecological theory and empirical research. On the basis of these requirements and the hypothesis that ecosystem risk is a function of the risk of its component species, we propose a set of four criteria: recent declines in distribution or ecological function, historical total loss in distribution or ecological function, small distribution combined with decline, or very small distribution. Most work has focused on terrestrial ecosystems, but comparable thresholds and criteria for freshwater and marine ecosystems are also needed. These are the first steps in an international consultation process that will lead to a unified proposal to be presented at the next World Conservation Congress in 2012. 相似文献
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FINN DANIELSEN HENDRIEN BEUKEMA† NEIL D. BURGESS‡§ FAIZAL PARISH CARSTEN A. BRÜHL†† PAUL F. DONALD‡‡ DANIEL MURDIYARSO§§ BEN PHALAN‡ LUCAS REIJNDERS MATTHEW STRUEBIG††† EMILY B. FITZHERBERT‡‡‡§§§ 《Conservation biology》2009,23(2):348-358
Abstract: The growing demand for biofuels is promoting the expansion of a number of agricultural commodities, including oil palm (Elaeis guineensis). Oil‐palm plantations cover over 13 million ha, primarily in Southeast Asia, where they have directly or indirectly replaced tropical rainforest. We explored the impact of the spread of oil‐palm plantations on greenhouse gas emission and biodiversity. We assessed changes in carbon stocks with changing land use and compared this with the amount of fossil‐fuel carbon emission avoided through its replacement by biofuel carbon. We estimated it would take between 75 and 93 years for the carbon emissions saved through use of biofuel to compensate for the carbon lost through forest conversion, depending on how the forest was cleared. If the original habitat was peatland, carbon balance would take more than 600 years. Conversely, planting oil palms on degraded grassland would lead to a net removal of carbon within 10 years. These estimates have associated uncertainty, but their magnitude and relative proportions seem credible. We carried out a meta‐analysis of published faunal studies that compared forest with oil palm. We found that plantations supported species‐poor communities containing few forest species. Because no published data on flora were available, we present results from our sampling of plants in oil palm and forest plots in Indonesia. Although the species richness of pteridophytes was higher in plantations, they held few forest species. Trees, lianas, epiphytic orchids, and indigenous palms were wholly absent from oil‐palm plantations. The majority of individual plants and animals in oil‐palm plantations belonged to a small number of generalist species of low conservation concern. As countries strive to meet obligations to reduce carbon emissions under one international agreement (Kyoto Protocol), they may not only fail to meet their obligations under another (Convention on Biological Diversity) but may actually hasten global climate change. Reducing deforestation is likely to represent a more effective climate‐change mitigation strategy than converting forest for biofuel production, and it may help nations meet their international commitments to reduce biodiversity loss. 相似文献
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We analyzed the relation of the amount and spatial pattern of land cover with stream fish communities, in-stream habitat,
and baseflow in 47 small southeastern Wisconsin, USA, watersheds encompassing a gradient of predominantly agricultural to
predominantly urban land uses. The amount of connected impervious surface in the watershed was the best measure of urbanization
for predicting fish density, species richness, diversity, and index of biotic integrity (IBI) score; bank erosion; and base
flow. However, connected imperviousness was not significantly correlated with overall habitat quality for fish. Nonlinear
models were developed using quantile regression to predict the maximum possible number of fish species, IBI score, and base
flow for a given level of imperviousness. At watershed connected imperviousness levels less than about 8%, all three variables
could have high values, whereas at connected imperviousness levels greater than 12% their values were inevitably low. Connected
imperviousness levels between 8 and 12% represented a threshold region where minor changes in urbanization could result in
major changes in stream condition. In a spatial analysis, connected imperviousness within a 50-m buffer along the stream or
within a 1.6-km radius upstream of the sampling site had more influence on stream fish and base flow than did comparable amounts
of imperviousness further away. Our results suggest that urban development that minimizes amount of connected impervious surface
and establishes undeveloped buffer areas along streams should have less impact than conventional types of development. 相似文献
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National Threatened Species Listing Based on IUCN Criteria and Regional Guidelines: Current Status and Future Perspectives 总被引:3,自引:0,他引:3
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Breeding Distributions of North American Bird Species Moving North as a Result of Climate Change 总被引:2,自引:0,他引:2
Abstract: Geographic changes in species distributions toward traditionally cooler climes is one hypothesized indicator of recent global climate change. We examined distribution data on 56 bird species. If global warming is affecting species distributions across the temperate northern hemisphere, these data should show the same northward range expansions of birds that have been reported for Great Britain. Because a northward shift of distributions might be due to multidirectional range expansions for multiple species, we also examined the possibility that birds with northern distributions may be expanding their ranges southward. There was no southward expansion of birds with a northern distribution, indicating that there is no evidence of overall range expansion of insectivorous and granivorous birds in North America. As predicted, the northern limit of birds with a southern distribution showed a significant shift northward (2.35 km/year). This northward shift is similar to that observed in previous work conducted in Great Britain: the widespread nature of this shift in species distributions over two distinct geographical regions and its coincidence with a period of global warming suggests a connection with global climate change. 相似文献
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Abstract: Conservation biology has provided wildlife managers with a wealth of concepts and tools for use in conservation planning; among them is the surrogate species concept. Over the past 20 years, a growing body of empirical literature has demonstrated the limited effectiveness of surrogates as management tools, unless it is first established that the target species and surrogate will respond similarly to a given set of environmental conditions. Wildlife managers and policy makers have adopted the surrogate species concept, reflecting the limited information available on most species at risk of extirpation or extinction and constraints on resources available to support conservation efforts. We examined the use of surrogate species, in the form of cross‐taxon response‐indicator species (that is, one species from which data are used to guide management planning for another, distinct species) in the Sacramento‐San Joaquin Delta, California (U.S.A.). In that system there has been increasing reliance on surrogates in conservation planning for species listed under federal or state endangered species acts, although the agencies applying the surrogate species concept did not first validate that the surrogate and target species respond similarly to relevant environmental conditions. During the same period, conservation biologists demonstrated that the surrogate concept is generally unsupported by ecological theory and empirical evidence. Recently developed validation procedures may allow for the productive use of surrogates in conservation planning, but, used without validation, the surrogate species concept is not a reliable planning tool. 相似文献