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1.
Trophic networks in small isolated islands are in a fragile balance, and their disturbance can easily contribute toward the extinction vortex of species. Here, we show, in a small Atlantic island (Raso) in the Cabo Verde Archipelago, using DNA metabarcoding, the extent of trophic dependence of the Endangered giant wall gecko Tarentola gigas on endemic populations of vertebrates, including one of the rarest bird species of the world, the Critically Endangered Raso lark Alauda razae. We found that the Raso lark (27%), Iago sparrow Passer iagoensis (12%), Bulwer's petrel Bulweria bulwerii (15%), and the Cabo Verde shearwater Calonectris edwardsii (10%) are the most frequent vertebrate signatures found in the feces of the giant wall gecko. This work provides the first integrative assessment of their trophic links, an important issue to be considered for the long‐term conservation of these small and isolated island ecosystems.  相似文献   

2.
Tulipa cypria, a Cyprus endemic plant, is protected under local and international legislations and categorised as “Endangered” by IUCN. Detailed habitat and distribution information was previously limited, particularly for northern Cyprus. Our objective was to accurately map the distribution and to collect habitat, subpopulation and threat data to enable a conservation status reassessment at global and regional levels. We gathered all available data and conducted extensive surveys focusing on northern Cyprus in 2014–2015, identifying 17 extant subpopulations amounting to 7765 individuals and the loss of 2 historical subpopulations amounting to 3500 individuals. We infer a continuous decline in population size and identify the major cause to be habitat loss through agriculture, with 75% of global habitats and 100% of northern Cyprus habitats being affected by it. We update the global assessment to Endangered B1ab(iii, iv, v) + B2ab(iii, iv, v) and suggest regional assessments for northern Cyprus (Endangered B1ab(iii, iv, v) + B2ab(iii, iv, v)), UN Buffer Zone (Endangered D1) and southern Cyprus (Endangered B2ab(iii)). Conservation priorities identified include initiation of gene transfer and life history studies, population trend monitoring and exsitu conservation actions.  相似文献   

3.
以《中国珍稀濒危保护植物名录》、《中国植物红皮书》、《国家重点保护野生植物名录(第一批)》、《中国物种红色名录》、《中国生物多样性红色名录(高等植物卷)》、《内蒙古珍稀濒危保护植物名录》和《内蒙古珍稀濒危植物图谱》中127种内蒙古珍稀濒危植物为研究对象,通过资料收集及专家咨询,构建了内蒙古珍稀濒危植物受威胁等级、优先保护评估体系.建立了濒危系数、遗传价值系数、利用价值系数、生境系数、繁殖系数5项准则,准则下共设17个指标;运用层次分析法确定指标体系权重,计算出珍稀濒危植物濒危等级及优先保护级别.结果表明: 极危种2种、濒危种13种、易危种37种、近危种44种、无危种31种,分别占总数的1.6%、10.2%、29.1%、34.7%、24.4%.其中,受威胁种(极危、濒危和易危种)共52种,占总种数的40.9%.一级保护植物35种、二级保护植物72种、三级保护植物20种,分别占总数的27.6%、56.7%、15.8%.本评估结果与《中国生物多样性红色名录(高等植物卷)》、《内蒙古珍稀濒危保护植物名录》相比,有75种植物的濒危等级和62种植物的保护级别发生了变化.其中新增了9种植物的濒危等级评估和32种植物的保护级别.  相似文献   

4.
基于文献和标本信息以及专家提供的数据, 依据中国大型真菌评估的标准和程序, 对中国范围内已知大型担子菌进行了受威胁状态评估。结果显示, 在评估的6,268种担子菌中, 受威胁(疑似灭绝、极危、濒危、易危)的物种有45种, 受威胁比例为0.72%。受威胁的大型担子菌物种中食药用菌比例达1/3以上, 且大部分物种仍无法人工栽培, 主要依赖野生资源。我国受威胁担子菌主要集中分布在西南和东北地区。人类活动导致的物种栖息地萎缩和破坏是我国大型担子菌受威胁的首要因子, 过度采挖是食药用菌受威胁的重要原因。此外, 数据不足的大型担子菌共4,251种, 占被评估大型担子菌总数的67.82%, 表明我国大型担子菌物种多样性及相关研究还存在不足。  相似文献   

5.
Over 1,000 mammal species are red-listed by IUCN, as Critically Endangered, Endangered or Vulnerable. Conservation of many threatened mammal species, even inside protected areas, depends on costly active day-to-day defence against poaching, bushmeat hunting, invasive species and habitat encroachment. Many parks agencies worldwide now rely heavily on tourism for routine operational funding: >50% in some cases. This puts rare mammals at a new risk, from downturns in tourism driven by external socioeconomic factors. Using the survival of individual animals as a metric or currency of successful conservation, we calculate here what proportions of remaining populations of IUCN-redlisted mammal species are currently supported by funds from tourism. This proportion is ≥5% for over half of the species where relevant data exist, ≥15% for one fifth, and up to 66% in a few cases. Many of these species, especially the most endangered, survive only in one single remaining subpopulation. These proportions are not correlated either with global population sizes or recognition as wildlife tourism icons. Most of the more heavily tourism-dependent species, however, are medium sized (>7.5 kg) or larger. Historically, biological concern over the growth of tourism in protected areas has centered on direct disturbance to wildlife. These results show that conservation of threatened mammal species has become reliant on revenue from tourism to a previously unsuspected degree. On the one hand, this provides new opportunities for conservation funding; but on the other, dependence on such an uncertain source of funding is a new, large and growing threat to red-listed species.  相似文献   

6.
To assess whether imperiled species are covered by existing protections in the biologically-rich state of Nevada, U.S.A., we compared the distribution of reserves with known imperiled species occurrences. For species poorly represented in reserves, we determined whether they were receiving alternate protection under the U.S. Endangered Species Act or voluntary conservation plans. A majority (212, 55%) of Nevada’s 384 imperiled species had fewer than 25% of occurrences in reserves and most (282, 68%) had fewer than 50% of occurrences in reserves. Of imperiled species with less than 25% or fewer than two occurrences in reserves, only 9% are currently receiving alternate protection from the Endangered Species Act or voluntary plans. These results suggest that providing protection for imperiled species in Nevada will require both an expansion of the existing reserve system, which currently covers 14% of the state, and protection of more species under the Endangered Species Act or other programs. By dividing Nevada into equal-sized hexagons and scoring each of these hexagons based on a rarity-weighted richness index of imperiled species occurrences, we identified 19 imperiled species hot spots in Nevada. No imperiled species occurrences were protected in seven (37%) and less than half were protected in 11 (58%) of these hot spots. Protecting these areas could provide important additional protection for imperiled species in Nevada. Evaluations of protective measures for biological diversity should include the full suite of protections, including both reserves and laws and regulations.  相似文献   

7.
No global synthesis of the status of baleen whales has been published since the 2008 IUCN Red List assessments. Many populations remain at low numbers from historical commercial whaling, which had ceased for all but a few by 1989. Fishing gear entanglement and ship strikes are the most severe current threats. The acute and long‐term effects of anthropogenic noise and the cumulative effects of multiple stressors are of concern but poorly understood. The looming consequences of climate change and ocean acidification remain difficult to characterize. North Atlantic and North Pacific right whales are among the species listed as Endangered. Southern right, bowhead, and gray whales have been assessed as Least Concern but some subpopulations of these species ‐ western North Pacific gray whales, Chile‐Peru right whales, and Svalbard/Barents Sea and Sea of Okhotsk bowhead whales ‐ remain at low levels and are either Endangered or Critically Endangered. Eastern North Pacific blue whales have reportedly recovered, but Antarctic blue whales remain at about 1% of pre‐exploitation levels. Small isolated subspecies or subpopulations, such as northern Indian Ocean blue whales, Arabian Sea humpback whales, and Mediterranean Sea fin whales are threatened while most subpopulations of sei, Bryde's, and Omura's whales are inadequately monitored and difficult to assess.  相似文献   

8.
The establishment of baseline IUCN Red List assessments for plants is a crucial step in conservation planning. Nowhere is this more important than in biodiversity hotspots that are subject to significant anthropogenic pressures, such as Madagascar. Here, all Madagascar palm species are assessed using the IUCN Red List categories and criteria, version 3.1. Our results indicate that 83% of the 192 endemic species are threatened, nearly four times the proportion estimated for plants globally and exceeding estimates for all other comprehensively evaluated plant groups in Madagascar. Compared with a previous assessment in 1995, the number of Endangered and Critically Endangered species has substantially increased, due to the discovery of 28 new species since 1995, most of which are highly threatened. The conservation status of most species included in both the 1995 and the current assessments has not changed. Where change occurred, more species have moved to lower threat categories than to higher categories, because of improved knowledge of species and their distributions, rather than a decrease in extinction risk. However, some cases of genuine deterioration in conservation status were also identified. Palms in Madagascar are primarily threatened by habitat loss due to agriculture and biological resource use through direct exploitation or collateral damage. The recent extension of Madagascar’s protected area network is highly beneficial for palms, substantially increasing the number of threatened species populations included within reserves. Notably, three of the eight most important protected areas for palms are newly designated. However, 28 threatened and data deficient species are not protected by the expanded network, including some Critically Endangered species. Moreover, many species occurring in protected areas are still threatened, indicating that threatening processes persist even in reserves. Definitive implementation of the new protected areas combined with local community engagement are essential for the survival of Madagascar’s palms.  相似文献   

9.
We present an annotated checklist for a total 241 reptiles and 22 amphibians including 5 frogs, 9 toads, 7 newts and salamanders, 1 crocodile, 1 worm lizard, 148 lizards, 79 snakes and 12 turtles and tortoises, includes the most scientific literature up to August 2014 and also based on several field surveys conducted in different Provinces of Iran from 2009 to 2014. We present an up-to-dated checklist of reptiles and amphibians in Iran. We provide a comprehensive listing of taxonomy, names, distribution and conservation status of all amphibians and reptiles of Iran. This checklist includes all recognized named taxa, English names for classes, orders, families, species, subspecies along with Persian names for species, including indication of native and introduced species. For the first time we report two non-native introduced reptiles from natural habitats of Iran. Of the total 22 species of amphibians in Iran, 6(27.2%) are endemic and of the total 241 species of reptiles, 55(22.8%) are endemic. Of the 22 amphibians species in Iran, 3(13%) are Critically Endangered, 2(9%) are Vulnerable and of the 241 reptile species 3(1.2%) are Critically Endangered, 4(1.6%) are Endangered and 10(4.1%) are Vulnerable. Accordingly, this paper combines significant aspects of taxonomy, common names, conservation status and distribution of the Iranian herpetofauna.  相似文献   

10.
Abstract

A Red List of all 108 Pezizomycotina (Ascomycota) species recorded in Umbria Region (central Italy) is provided. According to the IUCN categories and criteria, 60.18% of the assessed species are classified as threatened, whereas 12.96% are Near Threatened (NT), 1.86% are Least Concerned (LC) and a noteworthy amount of 25% are Data Deficient (DD). As a consequence of the downlisting applied to the majority of the assessed taxa, according to the guidelines for application of IUCN red list criteria at Regional level, only 1.54% of the threatened species is Critically Endangered (CR), while 46.15% are Endangered (EN) and 52.31% are Vulnerable (VU). Given that the present work represents the first complete regional red list of Pezizomycotina in Italy, and that a national, as well as a European red list do not exist to date, it could be considered as a case study for other Italian Regions as well as for other European countries, aiming at the compilation of a national and European red list of this fungal group mostly overlooked in conservation strategies.  相似文献   

11.
Tourism and recreation are large industries employing millions of people and contribute over US$2.01 trillion to the global economy. Unfortunately they also have diverse and sometimes severe environmental impacts affecting many species, including those that are rare and threatened. To assess the extent to which these industries threaten vascular plants, we reviewed data in the IUCN Red List for 462 Critically Endangered, Endangered and Vulnerable European species. Tourism and recreation were listed as threatening 42 % (194 species) of these species from across 50 families, mostly herbs (70 %). They were listed as threatening plants in 9 of the 10 bioregions in Europe and in 25 of the 40 countries assessed. Popular tourism destinations such as the Canary Islands (41 species) and mainland Spain (40 species) had the greatest diversity of species listed as threatened by tourism and recreation. The most common of these threats were trampling (61 species), plant collection (59), the maintenance/construction of tourist infrastructure (43) and habitat degradation due to the urbanisation of tourist sites (13). Additional species assessments and more research on the impacts of tourism and recreation may add to these values. It is clear that these industries pose an important threatening process on plants in Europe based on the IUCN Red List data and hence deserve greater recognition in terms of research, conservation and management.  相似文献   

12.
A global review of island endemic birds   总被引:2,自引:0,他引:2  
Although fewer than one-fifth of the world's bird species are restricted to islands, over 90% of bird extinctions during historic times have occurred on islands. The major identified cause has been the effects of exotic animal species introduced by man; the largest number of documented extinctions has occurred on islands of the Pacific Ocean.
Some 39% (402) of threatened bird species are restricted to islands and more than 907; of these are endemic to a single geopolitical unit. The largest numbers occurring in such units are in Indonesia (91) and the Philippines (34). As a region, the Pacific holds more threatened species (110) than any other, including almost half of those considered Endangered and over 40% of the Vulnerable species.
Most threatened island species are forest-dwelling. A high proportion of the Endangered species use seasonal/temperate forest. While habitat destruction now poses the greatest overall threat to island birds (affecting over half the species restricted to islands), the presence of introduced species threatens 30 of the 66 Endangered species.
Although immediate extinctions of island species can best be averted by mitigating the effects of introductions, the removal of native forests will be a more severe problem in the longer term. There is an urgent need for ecologists to provide detailed information on the habitats of both threatened and endemic species so that more appropriate and effective conservation programmes can be developed.  相似文献   

13.
We review the conservation status and threats to the endemic vascular flora of the Cape Verde islands, mostly based on the past two decades of collecting, literature review and herbarium specimens. The application of IUCN Red List criteria and categories using RAMAS software reveals that 78% of the endemic plants are threatened (29.3% Critically Endangered, 41.3% Endangered, 7.6% Vulnerable). Most of these endemics have a limited geographical range, and half of them have Areas of Occupancy and Extents of Occurrence of < 20 and 200 km2, respectively. Our data show that, over the last two decades, the Cape Verde vascular plants have become more threatened and their conservation status has declined, mostly as a consequence of the increase in exotic species, habitat degradation and human disturbance. This paper presents the first comprehensive IUCN Red List data review for the plants endemic to Cape Verde, thus providing an important step towards the recognition and conservation of its threatened endemic flora at the national and global level. It also fills a knowledge gap, as it represents the first thorough assessment of the conservation status of the entire endemic flora of a Macaronesian archipelago.  相似文献   

14.
15.
Marine molluscs represent an estimated 23% of all extant marine taxa, but research into their conservation status has so far failed to reflect this importance, with minimal inclusion on the authoritative Red List of the International Union for the Conservation of Nature (IUCN). We assessed the status of all 632 valid species of the tropical marine gastropod mollusc, Conus (cone snails), using Red List standards and procedures to lay the groundwork for future decadal monitoring, one of the first fully comprehensive global assessments of a marine taxon. Three-quarters (75.6%) of species were not currently considered at risk of extinction owing to their wide distribution and perceived abundance. However, 6.5% were considered threatened with extinction with a further 4.1% near threatened. Data deficiency prevented 13.8% of species from being categorised although they also possess characteristics that signal concern. Where hotspots of endemism occur, most notably in the Eastern Atlantic, 42.9% of the 98 species from that biogeographical region were classified as threatened or near threatened with extinction. All 14 species included in the highest categories of Critically Endangered and Endangered are endemic to either Cape Verde or Senegal, with each of the three Critically Endangered species restricted to single islands in Cape Verde. Threats to all these species are driven by habitat loss and anthropogenic disturbance, in particular from urban pollution, tourism and coastal development. Our findings show that levels of extinction risk to which cone snails are exposed are of a similar magnitude to those seen in many fully assessed terrestrial taxa. The widely held view that marine species are less at risk is not upheld.  相似文献   

16.
Import and export of primates is controlled by the Endangered Species Act and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Permits are required for all international transactions, and certain primates may not be traded at all for commercial permits.  相似文献   

17.
The application of environmental DNA (eDNA) metabarcoding as a biomonitoring tool has greatly increased, but studies have focused on temperate aquatic macro-organisms. We apply eDNA metabarcoding to detecting the mammalian community in two high-biodiversity regions of Brazil: the Amazon and Atlantic Forests. We identified Critically Endangered and Endangered mammalian species and found overlap with species identified via camera trapping. We highlight the potential for using eDNA monitoring for mammals in biodiverse regions and identify challenges: we need a better understanding of the ecology of eDNA within variable environments and more appropriate reference sequences for species identification in these anthropogenically impacted biomes.  相似文献   

18.
Sirenians have a unique ecological function in coastal ecosystems, deserving special conservation attention. The West Indian manatee (Trichechus manatus) is globally classified as Vulnerable by the IUCN. In Brazil, where the species was intensively hunted in the past and currently faces several threats, it was classified as Endangered during the last national assessment published in 2014. Here, we generated information based on available data to assess the species extinction risk in Brazil using IUCN regional guidelines, applying all criteria, and choosing the highest category of risk. Abundance at the national level was projected considering the density estimated in Ceará and Rio Grande do Norte states and the Criterion B EOO (Extent of Occurrence) estimated in this study (34,899 km2) and resulted in 1,047 individuals (95% CI: 538–2,038). Six scenarios of annual mortality were inferred and suspected based on evidence. We adopted a simple discrete logistic growth model to project population reduction in the past and future (three generations − 69 years) in 18 scenarios. Among the 18 projected scenarios, four resulted in extinction, six in decline and eight in population growth. Considering the low abundance bound, all scenarios indicate a reduction larger than 80% in population size, classifying the species as ‘Critically Endangered’ based on A4de. Reduction in EOO and abundance in the past classify the species as ‘Endangered’ based on A2c. The suspected number of mature animals (607;95% CI: 312–1,182) and the projected decline higher than 20% in two generations also classify the species as ‘Endangered’ based on C1 and ‘Vulnerable’ under D1. Our results indicate that information can be generated to produce more accurate assessments based on available data. The species national extinction risk needs to be reassessed, and the National Action Plan effectiveness evaluated.  相似文献   

19.
Abstract

Antirrhinum lopesianum Rothm. is a narrow endemic of the Lusitan Duriensean biogeographical sector (central western Spain and north-eastern Portugal). The species is listed as threatened in several Spanish documents, although it does not figure as such in any Portuguese document. This paper provides a detailed study of its distribution, estimates of the sizes of its populations, the threats it faces, and its current conservation status. The total number of individuals thought to exist is only 768, distributed along the valley of the River Duero on the Spanish – Portuguese border (562, 71.2%), and in the Portuguese Sabor River valley (206, 26.8%). The main threat to the species is loss of habitat: about one third of the Iberian populations can be considered threatened; one population containing 37.6% of all these plants (289) is severely threatened. To determine the Area of Occupancy and the Extent of Occurrence, an exhaustive bibliographical survey was carried out, and herbarium specimens deposited in several institutions were revised. It is, therefore, classifiable as Critically Endangered in Portugal and Endangered in Spain.  相似文献   

20.
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