Comprehensive Red List Assessment Reveals Exceptionally High Extinction Risk to Madagascar Palms

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.     

Comparing and contrasting threat assessments of plant species at the global and sub-global level

Evidence-based assessments of extinction risk are established tools used to inform the conservation of plant species, and form the basis of key targets within the framework of the Global Strategy for Plant Conservation (GSPC). An overall picture of plants threat assessments is challenging due to the use of a variety of methodologies and range in scope from global to subnational. In this study, we quantify the state of progress in assessing the extinction risk of all land plants, determine the key geographic and taxonomic gaps with respect to our understanding of plant extinction risk, and evaluate the impact of different sources and methodologies on the utility of plant assessments. To this end, we have analyzed a cleaned dataset compiled from IUCN Red List of Threatened Species and Regional Red Lists. We reveal that there are assessments available for 89,810 distinct species or 25% of all accepted land plant species. However unlike with other major organismal lineages the bulk of the plant species assessments are derived from Regional Red Lists, and not the Global IUCN Red List. We demonstrate that this bias towards regional assessments results in distinct taxonomic and geographic strengths and weaknesses, and we identify substantial taxonomic and geographic gaps in the assessment coverage. With species that have been assessed in common at both global and regional levels, we explore the implications of combining threat assessments from different sources. We find that half of global and regional assessments do not agree on the exact category of extinction risk for a species. Regional assessments assign a higher risk of extinction; or underestimate extinction risk with almost equal frequency. We conclude with recommended interventions, but support the suggestion that all threat assessments should be pooled to provide more data and broaden the scope of threat assessments for monitoring progress towards GSPC targets.     

Application of the IUCN Red Listing system to setting species targets for conservation planning purposes

Biodiversity targets, or estimates of the quantities of biodiversity features that should be conserved in a region, are fundamental to systematic conservation planning. We propose that targets for species should be based on the quantitative thresholds developed for the Vulnerable category of the IUCN Red List system, thereby avoiding future listings of species in an IUCN Red List threat category or an increase in the extinction risk, or ultimate extinction, of species already listed as threatened. Examples of this approach are presented for case studies from South Africa, including threatened taxa listed under the IUCN Red List criteria of A to D, a species listed as Near Threatened, a species of conservation concern due to its rarity, and one species in need of recovery. The method gives rise to multiple representation targets, an improvement on the often used single representation targets that are inadequate for long term maintenance of biodiversity or the arbitrary multiple representation and percentage targets that are sometimes adopted. Through the implementation of the resulting conservation plan, these targets will ensure that the conservation status of threatened species do not worsen over time by qualifying for higher categories of threat and may actually improve their conservation status by eliminating the threat of habitat loss and stabilizing population declines. The positive attributes ascribed to the IUCN Red List system, and therefore to the species targets arising from this approach, are important when justifying decisions that limit land uses known to be detrimental to biodiversity.     

Investing in evolutionary history: implementing a phylogenetic approach for mammal conservation

Under the impact of human activity, global extinction rates have risen a thousand times higher than shown in the fossil record. The resources available for conservation are insufficient to prevent the loss of much of the world's threatened biodiversity during this crisis. Conservation planners have been forced to prioritize their protective activities, in the context of great uncertainty. This has become known as 'the agony of choice'. A range of methods have been proposed for prioritizing species for conservation attention; one of the most strongly supported is prioritizing those species that maximize phylogenetic distinctiveness (PD). We evaluate how a composite measure of extinction risk and phylogenetic isolation (EDGE) has been used to prioritize species according to their degree of unique evolutionary history (evolutionary distinctiveness, ED) weighted by conservation urgency (global endangerment, GE). We review PD-based approaches and provide an updated list of EDGE mammals using the 2010 IUCN Red List. We evaluate how robust this method is to changes in phylogenetic uncertainty, knowledge of taxonomy and extinction risk, and examine how mammalian species that rank highly in EDGE score are representative of the collective from which they are drawn.     

Assessing changes in the conservation status of threatened Brazilian vertebrates

Threatened species assessments are one of the tools used to evaluate the degree of human impact on biodiversity, particularly in the assignment of extinction probabilities to individual species. Heavily altered habitats or biomes harbor a high proportion of the threatened species that have been assessed globally—80% of all of threatened species in IUCN’s Red List owe their poor status at least partly to the loss of habitat. Some taxonomic groups, however, may be well represented in the Red Lists either because they are naturally more sensitive to the most pervasive threats, or simply because they have been better studied. Here we look at the threat patterns on a temporal scale of Brazilian animal species included in the IUCN Red List, evaluating the hypotheses that directions of changes in red list status can be explained by the increase in scientific knowledge or by actual changes in threat factors. We analyzed changes in patterns of threatened vertebrates in IUCN’s list between 2002 and 2006. During that period, 120 species changed their status. 42 of these changes referred to inclusions and 78 to changes of threat category. For the latter group, 23 had their status upgraded to categories of higher threat, and 55 downgraded to others of lower threat. Most of the downgrades were caused by increase in scientific knowledge, while most of the upgrades resulted from the deterioration of the environmental conditions.     

Red Lists versus nature protection Acts: new analytical and numerical method to test threat trends

Red Lists are the widest international tool to establish species extinction risks and conservation priorities. Chronological Red Lists comparisons have proved a useful strategy to assess biodiversity loss. Alongside Red Lists, nature protection Acts have been enacted in most countries. The information transposition from Red Lists to Acts would be the logical sequence. However, the similarities between these (Red Lists—Acts) have never been analyzed. In this study, an innovative method based on IUCN categories is proposed to easily compare biodiversity protection catalogs. This international method could use data from any taxonomic group, area or date. Firstly, a matrix method was implemented which objectively weighs taxa threat degree, and incorporates a statistical significance value after catalog comparisons. Moreover, each catalog threat category trends are assessed through an analysis of their temporal evolution and the threat types of species categories. Thereby, the relationship between scientists’ Red Lists, and nature protection legislation enacted by governments can be established. A study performed from such perspective could provide useful tools for integrating and comparing information from different sources. This study was located in Andalusia (Spain), a hot spot with a long tradition in flora conservation, where a vast amount of information about this subject has been published. Cluster analysis results showed that catalog typology was the most influential feature in clustering, rather than the publication date or the geographical framework. The results also supported that the expected relationship between Red Lists and Acts was not consistent, and demonstrated that threat categories included in catalogs had oftentimes contradictory trends.     

IUCN受威胁物种红色名录进展及应用

IUCN受威胁物种红色名录已经成为世界上最全面的关于全球动物、真菌和植物物种灭绝风险状况的信息来源, 是生物多样性健康的关键指标, 是促进生物多样性保护和决策的有力工具。本文全面介绍IUCN受威胁物种红色名录(简称IUCN红色名录)的发展以及应用状况, 积极推动其在中国的物种评估和广泛应用。总结了IUCN红色名录从依赖于评估专家的主观意志决定物种濒危等级的濒危物种红皮书(Red Data Book)到IUCN受威胁物种等级和标准(3.1版)的客观量化和所有门类使用统一标准的过程。该等级体系可囊括全球所有物种, 其中“受威胁”的3个等级——极危(CR)、濒危(EN)或易危(VU)需使用5个标准进行量化评估, 对评估规范有非常严格的要求。该等级和标准体系不仅适用于全球层面, 同样也适用于地区层面物种评估, 只是在具体物种种群如果和周边其他地区(国家)存在种群交流情况时, 评估结果要进行调整。迄今为止, 全球层面使用该等级体系和标准评估了14万多种(其中在中国有分布的物种10,846种), 100多个国家和地方制定了地区/国家层面的红色名录, 中国红色名录评估了5.5万多种。IUCN红色名录已广泛应用于评估生物多样性变化速度; 为保护规划提供决策信息; 支持履行国际公约、修订国家/地区重点保护物种名录和自然保护地管理等; 指导资源有效合理分配和宣传教育等。广泛应用过程中, 讨论主要集中在获取数据的方法改进上; 另外, 一方面有专家认为标准存在缺陷需要完善, 另一方面有呼吁维持标准的长期相对稳定, 以便进行跨时间、跨区域、跨物种门类的比较。本文提出来了中国红色名录的持续机制和应用建议, 包括建立中国红色名录委员会、建立中国红色名录专业网站、发展评估专家队伍、建立中国红色名录评估更新机制, 以及加强国际协作、促进全球和中国红色名录的应用和发展。     

Phylogenetic diversity of Sri Lankan freshwater crabs and its implications for conservation

As part of a Global Biodiversity Hotspot, the conservation of Sri Lanka's endemic biodiversity warrants special attention. With 51 species (50 of them endemic) occurring in the island, the biodiversity of freshwater crabs is unusually high for such a small area (65 600 km²). Freshwater crabs have successfully colonized most moist habitats and all climatic and elevational zones in Sri Lanka. We assessed the biodiversity of these crabs in relation to the different elevational zones (lowland, upland and highland) based on both species richness and phylogenetic diversity. Three different lineages appear to have radiated simultaneously, each within a specific elevational zone, with little interchange thereafter. The lowland and upland zones show a higher species richness than the highland zone while – unexpectedly – phylogenetic diversity is highest in the lowland zone, illustrating the importance of considering both these measures in conservation planning. The diversity indices for the species in the various IUCN Red List categories in each of the three zones suggest that risk of extinction may be related to elevational zone. Our results also show that overall more than 50% of Sri Lanka's freshwater crab species (including several as yet undescribed ones), or approximately 72 million years of evolutionary history, are threatened with extinction.     

Automated assessment reveals that the extinction risk of reptiles is widely underestimated across space and phylogeny

The Red List of Threatened Species, published by the International Union for Conservation of Nature (IUCN), is a crucial tool for conservation decision-making. However, despite substantial effort, numerous species remain unassessed or have insufficient data available to be assigned a Red List extinction risk category. Moreover, the Red Listing process is subject to various sources of uncertainty and bias. The development of robust automated assessment methods could serve as an efficient and highly useful tool to accelerate the assessment process and offer provisional assessments. Here, we aimed to (1) present a machine learning–based automated extinction risk assessment method that can be used on less known species; (2) offer provisional assessments for all reptiles—the only major tetrapod group without a comprehensive Red List assessment; and (3) evaluate potential effects of human decision biases on the outcome of assessments. We use the method presented here to assess 4,369 reptile species that are currently unassessed or classified as Data Deficient by the IUCN. The models used in our predictions were 90% accurate in classifying species as threatened/nonthreatened, and 84% accurate in predicting specific extinction risk categories. Unassessed and Data Deficient reptiles were considerably more likely to be threatened than assessed species, adding to mounting evidence that these species warrant more conservation attention. The overall proportion of threatened species greatly increased when we included our provisional assessments. Assessor identities strongly affected prediction outcomes, suggesting that assessor effects need to be carefully considered in extinction risk assessments. Regions and taxa we identified as likely to be more threatened should be given increased attention in new assessments and conservation planning. Lastly, the method we present here can be easily implemented to help bridge the assessment gap for other less known taxa.

The Red List of Threatened Species, published by the IUCN, is a crucial tool for conservation decision making, but is subject to various sources of uncertainty and bias. Modelling the threat status of all global reptiles identifies increased threat to many groups of reptiles across many regions of the world, beyond those currently recognized; moreover, it highlights the effects of the IUCN assessment procedure on eventual threat categories.     

Use and misuse of the IUCN Red List Criteria in projecting climate change impacts on biodiversity

Recent attempts at projecting climate change impacts on biodiversity have used the IUCN Red List Criteria to obtain estimates of extinction rates based on projected range shifts. In these studies, the Criteria are often misapplied, potentially introducing substantial bias and uncertainty. These misapplications include arbitrary changes to temporal and spatial scales; confusion of the spatial variables; and assume a linear relationship between abundance and range area. Using the IUCN Red List Criteria to identify which species are threatened by climate change presents special problems and uncertainties, especially for shorter‐lived species. Responses of most species to future climate change are not understood well enough to estimate extinction risks based solely on climate change scenarios and projections of shifts and/or reductions in range areas. One way to further such understanding would be to analyze the interactions among habitat shifts, landscape structure and demography for a number of species, using a combination of models. Evaluating the patterns in the results might allow the development of guidelines for assigning species to threat categories, based on a combination of life history parameters, characteristics of the landscapes in which they live, and projected range changes.     

Extinction Risks and the Conservation of Madagascar's Reptiles

Background

An understanding of the conservation status of Madagascar''s endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island''s mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises.

Methodology/Principal Findings

Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas.

Conclusions/Significance

With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and western regions of Madagascar and this study highlights the importance of these arid regions to conserving the island''s biodiversity.     

Risk of extinction and categories of endangerment: perspectives from long-lived reptiles

The IUCN Red List of Threatened Animals is an important conservation tool, but the accuracy of predictions about risks of global extinction within 10 years or three generations is difficult to test objectively. In this study, we compare IUCN predictions with the results of attempts to derive realistic scenarios that could lead to the global extinction of six species of long-lived reptiles. For three species, the IUCN predictions matched real events reasonably well but still overestimated risks of global extinction. For the other species, the predictions did not match real events. Reasons why disparities occur are discussed. Received: February 16, 1999 / Accepted: December 27, 1999     

Using Red List Indices to measure progress towards the 2010 target and beyond

The World Conservation Union (IUCN) Red List is widely recognized as the most authoritative and objective system for classifying species by their risk of extinction. Red List Indices (RLIs) illustrate the relative rate at which a particular set of species change in overall threat status (i.e. projected relative extinction-risk), based on population and range size and trends as quantified by Red List categories. RLIs can be calculated for any representative set of species that has been fully assessed at least twice. They are based on the number of species in each Red List category, and the number changing categories between assessments as a result of genuine improvement or deterioration in status. RLIs show a fairly coarse level of resolution, but for fully assessed taxonomic groups they are highly representative, being based on information from a high proportion of species worldwide. The RLI for the world's birds shows that that their overall threat status has deteriorated steadily during the years 1988-2004 in all biogeographic realms and ecosystems. A preliminary RLI for amphibians for 1980-2004 shows similar rates of decline. RLIs are in development for other groups. In addition, a sampled index is being developed, based on a stratified sample of species from all major taxonomic groups, realms and ecosystems. This will provide extinction-risk trends that are more representative of all biodiversity.     

生态系统红色名录——一种新的生物多样性保护工具

生物多样性为人类提供了生存所必需的一系列生态系统服务和功能。然而,由于人为活动的加剧,生物多样性不断丧失。传统的生物多样性保护主要关注物种多样性,存在着对生物多样性的代表性不足,不能及时反应生态系统多样性的变化等缺点。近年来,生态系统层次上的多样性保护成为研究热点,一些国家和组织相继开展了大尺度的生态系统评估工作。文章回顾了已有的生态系统评估方案,发现当前生态系统评估多采用IUCN物种红色名录的分级标准体系,主要评估生态系统的濒危程度,评估标准主要是分布范围和功能的变化,不同评估方案采用的指标和阈值有差异,需要建立统一的生态系统分类体系和评价方案。同时,结合国内生态系统评价的现状,提出了在我国开展生态系统红色名录研究的若干可行建议。     

Diversity,distribution and conservation status assessment of Paraguayan palms (Arecaceae)

Indigenous palm species of Paraguay are presented with data on their diversity, distribution, threats and conservation status. The Paraguayan palm flora consists of 23 native species in 11 genera, representing two of the five subfamilies recognized in the group. The palm distribution in the country is strongly related to the different ecoregions present in Paraguay, with number of species by ecoregion being as follow: Cerrado (18), Upper Parana Atlantic forest (6), Wet Chaco (4), Pantanal (2), and Dry Chaco (1). Half of the species display an acaulescent habit reflecting an interesting ecological adaptation to natural fires in the Cerrado. The alarming rate of habitat modification that the country is undergoing since 1940s has put palms under a high risk of extinction in the wild. A GIS model was used to calculate the extent of occurrence and the area of occupancy of the species in order to assess their conservation status applying the IUCN Red List Categories and Criteria. This analysis shows that about 30% of the species are threatened; one species is Critically Endangered, three of them are Endangered, and three are Vulnerable. One species (Acrocomia hassleri) is considered Near Threatened, 13 are Least Concern whereas two species are insufficiently known and therefore unable to be assessed. Important areas for palm conservation in Paraguay were identified, revealing the importance of the Amambay department. Conservation measures for the threatened species identified are proposed.     

Measuring global trends in the status of biodiversity: red list indices for birds

The rapid destruction of the planet's biodiversity has prompted the nations of the world to set a target of achieving a significant reduction in the rate of loss of biodiversity by 2010. However, we do not yet have an adequate way of monitoring progress towards achieving this target. Here we present a method for producing indices based on the IUCN Red List to chart the overall threat status (projected relative extinction risk) of all the world's bird species from 1988 to 2004. Red List Indices (RLIs) are based on the number of species in each Red List category, and on the number changing categories between assessments as a result of genuine improvement or deterioration in status. The RLI for all bird species shows that their overall threat status has continued to deteriorate since 1988. Disaggregated indices show that deteriorations have occurred worldwide and in all major ecosystems, but with particularly steep declines in the indices for Indo-Malayan birds (driven by intensifying deforestation of the Sundaic lowlands) and for albatrosses and petrels (driven by incidental mortality in commercial longline fisheries). RLIs complement indicators based on species population trends and habitat extent for quantifying global trends in the status of biodiversity. Their main weaknesses are that the resolution of status changes is fairly coarse and that delays may occur before some status changes are detected. Their greatest strength is that they are based on information from nearly all species in a taxonomic group worldwide, rather than a potentially biased subset. At present, suitable data are only available for birds, but indices for other taxonomic groups are in development, as is a sampled index based on a stratified sample from all major taxonomic groups.     

Application of IUCN Red Listing Criteria at the Regional and National Levels: A Case Study from Central Asia

We assessed the threatened status of 163 Central Asian vertebrates using the IUCN Red List Criteria (Version 3.1) at the national and regional levels, and compared these assessments to the global assessments given in the IUCN 2002 Red List. We thus compared threat status at three spatial scales; national for five countries separately (Kazakhstan, Kyrgyzstan, Tadjikistan, Turkmenistan, Uzbekistan), regional for the five countries together, and global. This analysis was undertaken as a test of the applicability of IUCN criteria at the sub-global level. Generally the criteria worked well. In 4% of cases, the threat category was lower at the smaller scale of assessment. This was predominately caused by the use of decline rate criteria at the larger scale when populations at the smaller scale were stable. We also encountered issues with the listing of migratory species at the sub-global level. We used our data to carry out a preliminary assessment of Protected Area coverage in the region, and found evidence suggesting that threatened species and endemics are not well covered by the current protected area system.     

The Sampled Red List Index for Plants,phase II: ground-truthing specimen-based conservation assessments

The IUCN Sampled Red List Index (SRLI) is a policy response by biodiversity scientists to the need to estimate trends in extinction risk of the world''s diminishing biological diversity. Assessments of plant species for the SRLI project rely predominantly on herbarium specimen data from natural history collections, in the overwhelming absence of accurate population data or detailed distribution maps for the vast majority of plant species. This creates difficulties in re-assessing these species so as to measure genuine changes in conservation status, which must be observed under the same Red List criteria in order to be distinguished from an increase in the knowledge available for that species, and thus re-calculate the SRLI. However, the same specimen data identify precise localities where threatened species have previously been collected and can be used to model species ranges and to target fieldwork in order to test specimen-based range estimates and collect population data for SRLI plant species. Here, we outline a strategy for prioritizing fieldwork efforts in order to apply a wider range of IUCN Red List criteria to assessments of plant species, or any taxa with detailed locality or natural history specimen data, to produce a more robust estimation of the SRLI.     

Global assessment of extinction risk to populations of Sockeye salmon Oncorhynchus nerka

Background

Concern about the decline of wild salmon has attracted the attention of the International Union for the Conservation of Nature (IUCN). The IUCN applies quantitative criteria to assess risk of extinction and publishes its results on the Red List of Threatened Species. However, the focus is on the species level and thus may fail to show the risk to populations. The IUCN has adapted their criteria to apply to populations but there exist few examples of this type of assessment. We assessed the status of sockeye salmon Oncorhynchus nerka as a model for application of the IUCN population-level assessments and to provide the first global assessment of the status of an anadromous Pacific salmon.

Methods/Principal Findings

We found from demographic data that the sockeye salmon species is not presently at risk of extinction. We identified 98 independent populations with varying levels of risk within the species'' range. Of these, 5 (5%) are already extinct. We analyzed the risk for 62 out of 93 extant populations (67%) and found that 17 of these (27%) are at risk of extinction. The greatest number and concentration of extinct and threatened populations is in the southern part of the North American range, primarily due to overfishing, freshwater habitat loss, dams, hatcheries, and changing ocean conditions.

Conclusions/Significance

Although sockeye salmon are not at risk at the species-level, about one-third of the populations that we analyzed are at risk or already extinct. Without an understanding of risk to biodiversity at the level of populations, the biodiversity loss in salmon would be greatly underrepresented on the Red List. We urge government, conservation organizations, scientists and the public to recognize this limitation of the Red List. We also urge recognition that about one-third of sockeye salmon global population diversity is at risk of extinction or already extinct.