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1.
Conservation status, identification, distribution, abundance, habitat and ecology, threats, conservation actions and recommendations of a endemic bagrid catfish, Dianchi bullhead, Pseudobagrus medianalis were introduced based on data and knowledge from a GEF project in Lake Dianchi, Yunnan, China.  相似文献   
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Ditrichum cornubicum is a rare and threatened acrocarpous moss found on copper-rich mine waste, characteristic of the EU protected habitat ‘Calaminarian grassland of the Violetalia calaminariae’. The species was once thought to be a British endemic, being known from two former copper/tin mine sites in Cornwall, until the discovery of a population in 2006 at Allihies Mountain Mine, Co. Cork, Ireland, a former copper mine. In light of this discovery, two theories of possible introduction from Britain to Ireland were put forward: (1) an introduction from the 1800s and (2) a more recent introduction (2000s). Only male plants of the species are known, and reproduction and dispersal are therefore solely through asexual propagules and fragmentation. In order to address the conservation questions of the origin of the Irish population and to determine whether diversity exists within this rare species, genetic fingerprinting (amplified fragment length polymorphism) was carried out on the three known global populations. Percent polymorphism was found to be 7.29% and Nei's total gene diversity (HT) was 0.0356. AMOVA revealed that, of the small amount of variation found, the majority was among the three populations (98%). The presence of five private alleles in the Allihies population suggests a longer period of isolation than would fit either theory of introduction. Cluster analyses reveal that the Allihies population is more genetically distinct than the two British populations are to each other, thus heightening the conservation priority for this population.  相似文献   
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Alien species indicators provide vital information to the biodiversity policy sector on the status-quo and trends of biological invasions and on the efficacy of response measures. Applicable at different geographical scales and organizational levels, alien species indicators struggle with data availability and quality. Based on policy needs and previous work on the global scale, we here present a set of six alien species indicators for Europe, which capture complementary facets of biological invasions in Europe: (a) an combined index of invasion trends, (b) an indicator on pathways of invasions, (c) the Red List Index of Invasive Alien Species (IAS), (d) an indicator of IAS impacts on ecosystem services, (e) trends in incidence of livestock diseases and (f) an indicator on costs for alien species management and research. Each of these indicators has its particular strengths and shortcomings, but combined they allow for a nuanced understanding of the status and trends of biological invasions in Europe. We found that the scale and impact of biological invasions are steadily increasing across all impact indicators, although societal response in recent years has increased. The Red List Index is fit-for-purpose and demonstrates that overall extinction risks (here shown for amphibians in Europe) are increasing. Introduction pathway dynamics have changed, with some pathways decreasing in relevance (e.g., biological control agents) and others increasing (e.g., horticultural trade) providing a leverage for targeted policy and stakeholder response. The IAS indicators presented here for the first time on a continental basis serve as a starting point for future improvements, and as a basis for monitoring the efficacy of the recent EU legislation of IAS. This will need a better workflow for data collection and management. To achieve this, all main actors must work toward improving the interoperability among existing databases and between data holders.  相似文献   
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We assessed the size of the population of the African Softshell Turtle, Trionyx triunguis, in Dalaman (Mu?la, Turkey), which is considered to be the largest population of the species in the Mediterranean, by using the Jolly-Seber mark-recapture method. A total of 415 individuals were caught during the summer months of 2009 to 2011, of which 148 were recaptures. From 267 marked individuals, 148 (55%) were male, 69 (26%) were female and 50 (19%) were juveniles and subadults of indeterminate sex. The male:female ratio was calculated to be 2.14:1. By using Model A' of the Jolly-Seber mark-recapture method, which includes deaths but no immigration, the mean population size in Kükürt and Küçükdalyan (Karg?n) lakes, together with Tersakan and Ta?l?çay creeks, were estimated to be 396±36. Based on this estimation, the population density was calculated to be 14 turtles/ha. Approximately 67.4% of the estimated population was marked. The mean capture probability (p) and mean survival ratio (Φ) were 0.094±0.009 and 0.957±0.076, respectively. Our results showed that the species’ population size is larger than previously estimated based on visual counts. The status “Vulnerable” C2a of the IUCN Red Data Book categories seems therefore more appropriate for the Mediterranean subpopulation of Trionyx triunguis than “Endangered” C2a.  相似文献   
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Conservation status, identification, distribution, abundance, habitat and ecology, conservation actions and recommendations of a endemic cyprinid fish, Cyprinus micristius were introduced based on data and knowledge from a GEF project in Lake Dianchi, Yunnan, China.  相似文献   
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De Silva et al . (2007) present an overview of the distribution and conservation status of the endemic freshwater fish of Asia. Within that review they use data from the IUCN Red List of Threatened Species™ (2006) to conduct an analysis of the conservation status of those endemic fish species. Their analysis is incorrect and provides a very misleading impression of the level of threat to Asian freshwater fish and to freshwater fish at the global scale. The errors stem from a misinterpretation of the data presented on the IUCN Red List. The sources of errors are discussed below and the opportunity is taken to clarify what the information on the IUCN Red List represents.  相似文献   
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Analyses of knowledge gaps can highlight imbalances in research, encouraging greater proportionality in the distribution of research efforts. In this research we used generalized linear mixed models (GLMM) with the aim to determine if research efforts for the period 2005–2015 for terrestrial vertebrates of Amphibia, Aves, Mammalia and Reptilia in the South Pacific region were correlated with conservation status (critically endangered (CR), endangered (EN), vulnerable (VU), least concern (LC) and near threatened (NT)) or population trends (increasing, stable, decreasing and unknown) through the International Union for Conservation of Nature (IUCN) database. Our results showed that research distribution was uneven across different classes. Out of 633623 investigated papers, the average number of publications per species was 43.7, 306.7, 717.6 and 115.3 for Amphibia (284 species), Aves (1306 species), Mammalia (243 species) and Reptilia (400 species), respectively. Consistently, the lower publication effort on Amphibia compared to other taxonomic classes was revealed as significant by GLMM analysis. There was no significant differences in research effort among levels of conservation status. However, we found significantly different publication efforts among population trends of all examined species in that species with “unknown” population trends gained significantly lower researchers’ attention compared to species with “decreasing” trend. Results also indicated that, although it was not significant, the highest attention is given to species with “increasing” population trend over all taxonomic classes. Using the Information Theoretic approach we also generated a set of competing models to identify most important factors influencing research efforts, revealing that the highest ranked model included taxonomic class and population trend.  相似文献   
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濒危物种保护是生物多样性保护工作的重要组成部分, 而物种受威胁等级评估则是濒危物种保护的方向指引。经过多年的发展, 物种受威胁等级的评估由定性评估逐渐向定量评估为主、定性评估为辅的方向发展。本文综述了国内植物受威胁等级定量评估系统的研究进展, 同时介绍了国外较为成熟的IUCN红色名录评估系统、CITES评估系统、美国自然保育协会评估系统, 提出未来制定受威胁物种定量评估标准时要兼顾以下方面: (1)等级设置定义要明确、统一且合理; (2)评估标准应该定量化、客观且不冗余; (3)评估系统应该适应不同地理范围, 最好能同时表达出各范围的受威胁等级; (4)评估指标要包含物种动态信息, 能定量分析物种在过去或者未来的变化。此外, 本文认为国内的物种受威胁等级定量评估系统应该形成规范化的大纲, 加大宣传力度, 尽量将理论研究与具体的保护行动结合起来; 同时, 我国还应该采用全球广泛应用的受威胁等级评估系统获取物种受威胁等级, 将国内生物多样性保护工作纳入到全球范围中去。  相似文献   
10.
Climate change is expected to strongly affect freshwater fish communities. Combined with other anthropogenic drivers, the impacts may alter species spatio‐temporal distributions and contribute to population declines and local extinctions. To provide timely management and conservation of fishes, it is relevant to identify species that will be most impacted by climate change and those that will be resilient. Species traits are considered a promising source of information on characteristics that influence resilience to various environmental conditions and impacts. To this end, we collated life‐history traits and climatic niches of 443 European freshwater fish species and compared those identified as susceptible to climate change to those that are considered to be resilient. Significant differences were observed between the two groups in their distribution, life history, and climatic niche, with climate‐change‐susceptible species being distributed within the Mediterranean region, and being characterized by greater threat levels, lesser commercial relevance, lower vulnerability to fishing, smaller body and range size, and warmer thermal envelopes. Based on our results, we establish a list of species of highest priority for further research and monitoring regarding climate‐change susceptibility within Europe. The presented approach represents a promising tool to efficiently assess large groups of species regarding their susceptibility to climate change and other threats, and to identify research and management priorities.  相似文献   
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