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Abstract:  The exploitation and sale of wildlife species that are endangered in only part of their range present regulators with the critical challenge of separating legal from illegal takes. Wildlife DNA registers created from tissue samples of legally obtained individual wildlife specimens can address this problem by allowing managers to identify unregistered (presumably illegally obtained) specimens. We tested the effectiveness of the only current, fully operational wildlife DNA register of individual genetic profiles collected from legally caught minke whales ( Balaenoptera acutorostrata ). Twenty minke whale tissue samples collected at markets in Norway and 2 additional samples collected from beached minke whales in Denmark were genotyped at 12 loci used by the Norwegian minke whale DNA register. Genetic profiles of these samples then were compared against the 2676 individual profiles deposited in the Norwegian register. The high number of genetic markers used to identify individuals in our study allowed consistent matching of sample and reference profiles despite an overall error rate (due to experimental and interlaboratory data standardization) estimated at 0.015 per locus. Of the 22 test samples only the 2 Danish samples failed to match an existing profile in the Norwegian minke whale DNA register. Our results show that the basic principle of wildlife DNA registers can work in a real-life situation. The strength of wildlife DNA registers lies in their ability to unambiguously identify unregistered specimens with the aid of sensitive genetic methods that enable analysis of highly processed or degraded tissue samples. Our study also highlights a number of methodological problems such as laboratory errors and interlaboratory data standardization, which need be addressed to ensure a successful implementation of wildlife DNA registers.  相似文献   
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Monitoring and Evaluation in Conservation: a Review of Trends and Approaches   总被引:12,自引:0,他引:12  
Abstract:  There is growing recognition among conservation practitioners and scholars that good project management is integrally linked to well-designed monitoring and evaluation systems. Most conservation organizations have attempted to develop and implement monitoring and evaluation systems, often with mixed results. One problem seems to be that organizations are trying to build their systems from scratch, overlooking lessons learned from the many efforts to develop useful and practical monitoring and evaluation approaches. Thus, we undertook a review of monitoring and evaluation approaches in conservation and other fields including international development, public health, family planning, education, social services, and business. Here, we present our results for the field of conservation. We categorized the considerable variety of monitoring and evaluation approaches into four broad purposes: basic research; accounting and certification; status assessment; and effectiveness measurement. We focus here on status assessment and effectiveness measurement. Specific lessons that emerged follow: different monitoring and evaluation needs require different approaches; conceptual similarities are widespread among prevailing approaches; inconsistent language impedes communication; confusion among monitoring and evaluation components hinders practitioner ability to choose the appropriate component; and monitoring only quantitative biological variables is insufficient. We suggest that the conservation community continue support of collaborative initiatives to improve monitoring and evaluation, establish clear definitions of commonly used terms, clarify monitoring and evaluation system components, apply available approaches appropriately, and include qualitative and social variables in monitoring efforts.  相似文献   
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Abstract: Inventories of tree species are often conducted to guide conservation efforts in tropical forests. Such surveys are time consuming, demanding of expertise, and expensive to perform and interpret. Approaches to make survey efforts simpler or more effective would be valuable. In particular, it would be good to be able to easily identify areas of old‐growth forest. The average density of the wood of a tree species is closely linked to its successional status. We used tree inventory data from eastern Borneo to determine whether wood density can be used to quantify forest disturbance and conservation importance. The average density of wood in a plot was significantly and negatively related to disturbance levels, with plots with higher wood densities occurring almost exclusively in old‐growth forests. Average wood density was unimodally related to the diversity of tree species, indicating that the average wood density in a plot might be a better indicator of old‐growth forest than species diversity. In addition, Borneo endemics had significantly heavier wood than species that are common throughout the Malesian region, and they were more common in plots with higher average wood density. We concluded that wood density at the plot level could be a powerful tool for identifying areas of conservation priority in the tropical rain forests of Southeast Asia.  相似文献   
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