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141.
Assessment of the Environmental Risk Posed by an Exotic Fish: The Proposed Introduction of Channel Catfish (Ictalurus punctatus) to New Zealand 总被引:1,自引:0,他引:1
Abstract: In 1987, a proposal was made to introduce channel catfish (Ictalurus punctatus) into New Zealand for aquaculture. An environmental impact assessment in support of the proposal incorporated details of channel catfish biology, its value to people, diseases, the history of introductions elsewhere, and possible impacts on New Zealand biota should the species become established in the wild. Although information on the environmental impacts of channel catfish introduced to other countries was limited and inadequate for assessing potential effects on freshwater ecosystems in New Zealand, a permit was granted to import fertilized eggs. These were hatched in quarantine, and subject to the favorable outcome of environmental trials were to be released for aquaculture. Subsequently, the requirement for trials was abandoned and instead an independent, two-man review team (the authors) was appointed to advise the Minister of Fisheries on whether the environmental risk posed by channel catfish was acceptable. The team considered the impact assessment and additional submissions from interested parties. The team concluded that there was a high probability that fish would escape and that they would be capable of breeding and growing in a wide range of freshwater environments throughout much of New Zealand. Because channel catfish are omnivorous, they would probably prey on at least some native fish species and introduced salmonids, invertebrates including freshwater crayfish, and aquatic macrophytes. Competition to the detriment of other fishes was also considered likely. Furthermore, the low species diversity and ecological simplicity of fish communities in New Zealand could allow channel catfish opportunities not found within their natural range, as in parts of western North America where they have had significant impacts on freshwater communities. Because the evidence indicated that one or more valued species was likely to suffer a decline in abundance or distribution if channel catfish were introduced, the review team recommended that the environmental risk posed by the fish was unacceptable. The recommendation was accepted by the Minister of Fisheries and all the channel catfish held in quarantine were destroyed. This case clearly demonstrated weaknesses in the importation procedure in New Zealand and subsequently some changes have been made. In general, we recommend a four-step importation procedure comprising (1) environmental impact assessment, (2) publicity, (3) independent review, and (4) implementation. We suggest that the second step is most crucial. 相似文献
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143.
The Consistency of Extinction Risk Classification Protocols 总被引:1,自引:0,他引:1
TRACEY J. REGAN MARK A. BURGMAN† MICHAEL A. McCARTHY ‡ LAWRENCE L. MASTER§ DAVID A. KEITH GEORGINA M. MACE†† SANDY J. ANDELMAN‡‡ 《Conservation biology》2005,19(6):1969-1977
Abstract: Systematic protocols that use decision rules or scores are seen to improve consistency and transparency in classifying the conservation status of species. When applying these protocols, assessors are typically required to decide on estimates for attributes that are inherently uncertain. Input data and resulting classifications are usually treated as though they are exact and hence without operator error. We investigated the impact of data interpretation on the consistency of protocols of extinction risk classifications and diagnosed causes of discrepancies when they occurred. We tested three widely used systematic classification protocols employed by the World Conservation Union, NatureServe, and the Florida Fish and Wildlife Conservation Commission. We provided 18 assessors with identical information for 13 different species to infer estimates for each of the required parameters for the three protocols. The threat classification of several of the species varied from low risk to high risk, depending on who did the assessment. This occurred across the three protocols investigated. Assessors tended to agree on their placement of species in the highest (50–70%) and lowest risk categories (20–40%), but there was poor agreement on which species should be placed in the intermediate categories. Furthermore, the correspondence between the three classification methods was unpredictable, with large variation among assessors. These results highlight the importance of peer review and consensus among multiple assessors in species classifications and the need to be cautious with assessments carried out by a single assessor. Greater consistency among assessors requires wide use of training manuals and formal methods for estimating parameters that allow uncertainties to be represented, carried through chains of calculations, and reported transparently. 相似文献
144.
Conservation and Community Benefits from Traditional Coral Reef Management at Ahus Island, Papua New Guinea 总被引:6,自引:0,他引:6
Abstract: We investigated traditional coral reef management practices at Ahus Island, Manus Province, Papua New Guinea, to evaluate their social role in the community and potential to conserve reef ecosystems. For generations, Ahus Islanders have prohibited spear and net fishing within six delineated areas of their reef lagoon. One to three times per year, fish are briefly harvested from the restricted areas to provide food for ceremonial occasions. Underwater visual censuses of fishes revealed a significantly greater biomass and average size of target species within the restricted areas (205 kg/ha ± 20 [SE]; 102 mm TL [total length]± 0.7) compared with areas without fishing restrictions (127 kg/ha ± 13 SE; 85 mm TL ± 0.7). We estimated the biomass of fish removed during one of the harvest events was 5 to 10% of the available biomass within the restricted area, and in underwater visual surveys conducted before and after a harvesting event we detected no effect of harvesting on fish stocks. Compliance with the fishing restriction is attributed to its perceived legitimacy, its ability to provide the community with direct and indirect benefits, and its reflection of local socioeconomic circumstances. Limited-take closure systems that can serve the needs of a community may provide a viable conservation alternative in situations where compliance with fully closed protected-area regulations is low and resources for proper enforcement are untenable. 相似文献
145.
目前在中国,为环境保护目的建立“公益诉讼”制度的提法正吸引着人们极大的兴趣。特别是在2005年12月。国务院作出“关于落实科学发展观加强环境保护的决定”之后。“决定”中把推动环境公益诉讼作为长期改善中国环境保护体制的主要措施之一。就中国的公益诉讼应该采取哪种形式的问题。政府官员、学者、律师和NGO对此争论颇多。美国环境诉讼中采取的“公民诉讼(citizen suit)”制度作为诸多途径中的一种受到了特别关注。 相似文献
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BENIS N. EGOH BELINDA REYERS JOSIE CARWARDINE MICHAEL BODE PATRICK J. O'FARRELL KERRIE A. WILSON HUGH P. POSSINGHAM MATHIEU ROUGET WILLEM
De LANGE DAVID M. RICHARDSON RICHARD M. COWLING 《Conservation biology》2010,24(4):1021-1030
Abstract: Global declines in biodiversity and the widespread degradation of ecosystem services have led to urgent calls to safeguard both. Responses to this urgency include calls to integrate the needs of ecosystem services and biodiversity into the design of conservation interventions. The benefits of such integration are purported to include improvements in the justification and resources available for these interventions. Nevertheless, additional costs and potential trade‐offs remain poorly understood in the design of interventions that seek to conserve biodiversity and ecosystem services. We sought to investigate the synergies and trade‐offs in safeguarding ecosystem services and biodiversity in South Africa's Little Karoo. We used data on three ecosystem services—carbon storage, water recharge, and fodder provision—and data on biodiversity to examine several conservation planning scenarios. First, we investigated the amount of each ecosystem service captured incidentally by a conservation plan to meet targets for biodiversity only while minimizing opportunity costs. We then examined the costs of adding targets for ecosystem services into this conservation plan. Finally, we explored trade‐offs between biodiversity and ecosystem service targets at a fixed cost. At least 30% of each ecosystem service was captured incidentally when all of biodiversity targets were met. By including data on ecosystem services, we increased the amount of services captured by at least 20% for all three services without additional costs. When biodiversity targets were reduced by 8%, an extra 40% of fodder provision and water recharge were obtained and 58% of carbon could be captured for the same cost. The opportunity cost (in terms of forgone production) of safeguarding 100% of the biodiversity targets was about US$500 million. Our results showed that with a small decrease in biodiversity target achievement, substantial gains for the conservation of ecosystem services can be achieved within our biodiversity priority areas for no extra cost. 相似文献
148.
Neglect of Genetic Diversity in Implementation of the Convention on Biological Diversity 总被引:1,自引:0,他引:1
LINDA LAIKRE FRED W. ALLENDORF LAUREL C. ARONER C. SCOTT BAKER DAVID P. GREGOVICH MICHAEL M. HANSEN JENNIFER A. JACKSON KATHERINE C. KENDALL KEVIN McKELVEY MAILE C. NEEL ISABELLE OLIVIERI NILS RYMAN MICHAEL K. SCHWARTZ RUTH SHORT BULL JEFFREY B. STETZ DAVID A. TALLMON BARBARA L. TAYLOR CHRISTINA D. VOJTA DONALD M. WALLER ROBIN S. WAPLES 《Conservation biology》2010,24(1):86-88
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150.
Local Participation in Natural Resource Monitoring: a Characterization of Approaches 总被引:3,自引:0,他引:3
FINN DANIELSEN NEIL D. BURGESS ANDREW BALMFORD PAUL F. DONALD MIKKEL FUNDER JULIA P. G. JONES PHILIP ALVIOLA DANILO S. BALETE TOM BLOMLEY JUSTIN BRASHARES BRIAN CHILD MARTIN ENGHOFF JON FJELDSÅ SUNE HOLT HANNE HÜBERTZ ARNE E. JENSEN PER M. JENSEN JOHN MASSAO MARLYNN M. MENDOZA YONIKA NGAGA MICHAEL K. POULSEN RICARDO RUEDA MOSES SAM THOMAS SKIELBOE GREG STUART‐HILL ELMER TOPP‐JØRGENSEN DEKI YONTEN 《Conservation biology》2009,23(1):31-42
Abstract: The monitoring of trends in the status of species or habitats is routine in developed countries, where it is funded by the state or large nongovernmental organizations and often involves large numbers of skilled amateur volunteers. Far less monitoring of natural resources takes place in developing countries, where state agencies have small budgets, there are fewer skilled professionals or amateurs, and socioeconomic conditions prevent development of a culture of volunteerism. The resulting lack of knowledge about trends in species and habitats presents a serious challenge for detecting, understanding, and reversing declines in natural resource values. International environmental agreements require signatories undertake systematic monitoring of their natural resources, but no system exists to guide the development and expansion of monitoring schemes. To help develop such a protocol, we suggest a typology of monitoring categories, defined by their degree of local participation, ranging from no local involvement with monitoring undertaken by professional researchers to an entirely local effort with monitoring undertaken by local people. We assessed the strengths and weaknesses of each monitoring category and the potential of each to be sustainable in developed or developing countries. Locally based monitoring is particularly relevant in developing countries, where it can lead to rapid decisions to solve the key threats affecting natural resources, can empower local communities to better manage their resources, and can refine sustainable‐use strategies to improve local livelihoods. Nevertheless, we recognize that the accuracy and precision of the monitoring undertaken by local communities in different situations needs further study and field protocols need to be further developed to get the best from the unrealized potential of this approach. A challenge to conservation biologists is to identify and establish the monitoring system most relevant to a particular situation and to develop methods to integrate outputs from across the spectrum of monitoring schemes to produce wider indices of natural resources that capture the strengths of each. 相似文献