Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
PLoS One ; 19(9): e0306813, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39236015

RESUMO

Here, we summarise the extinction risk of the sharks and rays endemic to coastal, shelf, and slope waters of the southwest Indian Ocean and adjacent waters (SWIO+, Namibia to Kenya, including SWIO islands). This region is a hotspot of endemic and evolutionarily distinct sharks and rays. Nearly one-fifth (n = 13 of 70, 18.6%) of endemic sharks and rays are threatened, of these: one is Critically Endangered, five are Endangered, and seven are Vulnerable. A further seven (10.0%) are Near Threatened, 33 (47.1%) are Least Concern, and 17 (24.3%) are Data Deficient. While the primary threat is overfishing, there are the first signs that climate change is contributing to elevated extinction risk through habitat reduction and inshore distributional shifts. By backcasting their status, few endemic species were threatened in 1980, but this changed soon after the emergence of targeted shark and ray fisheries. South Africa has the highest national conservation responsibility, followed by Mozambique and Madagascar. Yet, while fisheries management and enforcement have improved in South Africa over recent decades, substantial improvements are urgently needed elsewhere. To avoid extinction and ensure robust populations of the region's endemic sharks and rays and maintain ecosystem functionality, there is an urgent need for the strict protection of Critically Endangered and Endangered species and sustainable management of Vulnerable, Near Threatened, and Least Concern species, underpinned by species-level data collection and reduction of incidental catch.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Extinção Biológica , Tubarões , Rajidae , Animais , Tubarões/fisiologia , Oceano Índico , Pesqueiros , Ecossistema
2.
PLoS One ; 18(11): e0293083, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37939028

RESUMO

Biodiversity loss is a major global challenge and minimizing extinction rates is the goal of several multilateral environmental agreements. Policy decisions require comprehensive, spatially explicit information on species' distributions and threats. We present an analysis of the conservation status of 14,669 European terrestrial, freshwater and marine species (ca. 10% of the continental fauna and flora), including all vertebrates and selected groups of invertebrates and plants. Our results reveal that 19% of European species are threatened with extinction, with higher extinction risks for plants (27%) and invertebrates (24%) compared to vertebrates (18%). These numbers exceed recent IPBES (Intergovernmental Platform on Biodiversity and Ecosystem Services) assumptions of extinction risk. Changes in agricultural practices and associated habitat loss, overharvesting, pollution and development are major threats to biodiversity. Maintaining and restoring sustainable land and water use practices is crucial to minimize future biodiversity declines.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , Vertebrados , Invertebrados , Plantas , Extinção Biológica , Espécies em Perigo de Extinção
3.
Conserv Biol ; 36(2): e13854, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34669223

RESUMO

Hydrothermal vents are rare deep-sea oases that house faunal assemblages with a similar density of life as coral reefs. Only approximately 600 of these hotspots are known worldwide, most only one-third of a football field in size. With advancing development of the deep-sea mining industry, there is an urgent need to protect these unique, insular ecosystems and their specialist endemic faunas. We applied the IUCN (International Union for the Conservation of Nature) Red List criteria to assess the extinction risk of vent-endemic molluscs with varying exposure to potential deep-sea mining. We assessed 31 species from three key areas under different regulatory frameworks in the Indian, West Pacific, and Southern Oceans. Three vent mollusc species were also examined as case studies of different threat contexts (protected or not from potential mining) to explore the interaction of local regulatory frameworks and IUCN Red List category assignment. We found that these assessments were robust even when there was some uncertainty in the total range of individual species, allowing assessment of species that have only recently been named and described. For vent-endemic species, regulatory changes to area-based management can have a greater impact on IUCN Red List assessment outcomes than incorporating additional data about species distributions. Our approach revealed the most useful IUCN Red List criteria for vent-endemic species: criteria B and D2. This approach, combining regulatory framework and distribution, has the potential to rapidly gauge assessment outcomes for species in insular systems worldwide.


Evaluación del Riesgo de Extinción de Especies Marinas Insulares Poco Estudiadas Resumen Los respiraderos hidrotermales son oasis poco comunes en las profundidades del mar en donde se encuentran conjuntos de fauna con una densidad similar a la de los arrecifes de coral. A nivel mundial, sólo se conocen aproximadamente 600 de estos puntos calientes, la mayoría solamente del tamaño de un tercio de una cancha de fútbol. Conforme avanza el desarrollo de la industria minera en mares profundos, también hay una urgente necesidad por proteger estos ecosistemas únicos e insulares y a su fauna endémica especialista. Aplicamos el criterio de la Lista Roja de la UICN (Unión Internacional para la Conservación de la Naturaleza) para evaluar el riesgo de extinción que tienen los moluscos endémicos de los respiraderos ante una exposición variable a la potencial minería de mar profundo. Evaluamos 31 especies de tres áreas importantes bajo diferentes marcos regulatorios en los océanos Índico, Pacífico Occidental y del Sur. Analizamos tres especies de moluscos de los respiraderos como estudios de caso para diferentes contextos de amenazas (protegidas o no de la minería potencial) para explorar la interacción de los marcos regulatorios locales y la clasificación categórica dentro de la Lista Roja de la UICN. Descubrimos que estos análisis eran sólidos incluso cuando existía algo de incertidumbre en cuanto a la extensión total de la especie individual, lo que permite la valoración de especies que han sido descritas y nombradas recientemente. Para las especies endémicas de las chimeneas, los cambios regulatorios a un manejo basado en el área pueden tener un mayor impacto sobre los resultados de evaluación de la Lista Roja de la UICN que la incorporación de datos adicionales sobre la distribución de las especies. Nuestra estrategia reveló los criterios más útiles de la Lista Roja de la UICN para las especies endémicas de las chimeneas: los criterios B y D2. Esta estrategia, que combina un marco regulatorio con la distribución, tiene el potencial para medir rápidamente los resultados de las evaluaciones para las especies que se encuentran en sistemas insulares en todo el mundo.


Assuntos
Espécies em Perigo de Extinção , Extinção Biológica , Animais , Conservação dos Recursos Naturais , Ecossistema , Oceanos e Mares
5.
Curr Biol ; 31(21): 4773-4787.e8, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34492229

RESUMO

The scale and drivers of marine biodiversity loss are being revealed by the International Union for Conservation of Nature (IUCN) Red List assessment process. We present the first global reassessment of 1,199 species in Class Chondrichthyes-sharks, rays, and chimeras. The first global assessment (in 2014) concluded that one-quarter (24%) of species were threatened. Now, 391 (32.6%) species are threatened with extinction. When this percentage of threat is applied to Data Deficient species, more than one-third (37.5%) of chondrichthyans are estimated to be threatened, with much of this change resulting from new information. Three species are Critically Endangered (Possibly Extinct), representing possibly the first global marine fish extinctions due to overfishing. Consequently, the chondrichthyan extinction rate is potentially 25 extinctions per million species years, comparable to that of terrestrial vertebrates. Overfishing is the universal threat affecting all 391 threatened species and is the sole threat for 67.3% of species and interacts with three other threats for the remaining third: loss and degradation of habitat (31.2% of threatened species), climate change (10.2%), and pollution (6.9%). Species are disproportionately threatened in tropical and subtropical coastal waters. Science-based limits on fishing, effective marine protected areas, and approaches that reduce or eliminate fishing mortality are urgently needed to minimize mortality of threatened species and ensure sustainable catch and trade of others. Immediate action is essential to prevent further extinctions and protect the potential for food security and ecosystem functions provided by this iconic lineage of predators.


Assuntos
Tubarões , Animais , Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Extinção Biológica , Pesqueiros
6.
PLoS One ; 11(8): e0160640, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27529491

RESUMO

Knowledge products comprise assessments of authoritative information supported by standards, governance, quality control, data, tools, and capacity building mechanisms. Considerable resources are dedicated to developing and maintaining knowledge products for biodiversity conservation, and they are widely used to inform policy and advise decision makers and practitioners. However, the financial cost of delivering this information is largely undocumented. We evaluated the costs and funding sources for developing and maintaining four global biodiversity and conservation knowledge products: The IUCN Red List of Threatened Species, the IUCN Red List of Ecosystems, Protected Planet, and the World Database of Key Biodiversity Areas. These are secondary data sets, built on primary data collected by extensive networks of expert contributors worldwide. We estimate that US$160 million (range: US$116-204 million), plus 293 person-years of volunteer time (range: 278-308 person-years) valued at US$ 14 million (range US$12-16 million), were invested in these four knowledge products between 1979 and 2013. More than half of this financing was provided through philanthropy, and nearly three-quarters was spent on personnel costs. The estimated annual cost of maintaining data and platforms for three of these knowledge products (excluding the IUCN Red List of Ecosystems for which annual costs were not possible to estimate for 2013) is US$6.5 million in total (range: US$6.2-6.7 million). We estimated that an additional US$114 million will be needed to reach pre-defined baselines of data coverage for all the four knowledge products, and that once achieved, annual maintenance costs will be approximately US$12 million. These costs are much lower than those to maintain many other, similarly important, global knowledge products. Ensuring that biodiversity and conservation knowledge products are sufficiently up to date, comprehensive and accurate is fundamental to inform decision-making for biodiversity conservation and sustainable development. Thus, the development and implementation of plans for sustainable long-term financing for them is critical.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/economia , Custos e Análise de Custo , Internacionalidade , Bases de Dados Factuais
7.
Nat Plants ; 1: 15142, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-27251394

RESUMO

A high proportion of plant species is predicted to be threatened with extinction in the near future. However, the threat status of only a small number has been evaluated compared with key animal groups, rendering the magnitude and nature of the risks plants face unclear. Here we report the results of a global species assessment for the largest plant taxon evaluated to date under the International Union for Conservation of Nature (IUCN) Red List Categories and Criteria, the iconic Cactaceae (cacti). We show that cacti are among the most threatened taxonomic groups assessed to date, with 31% of the 1,478 evaluated species threatened, demonstrating the high anthropogenic pressures on biodiversity in arid lands. The distribution of threatened species and the predominant threatening processes and drivers are different to those described for other taxa. The most significant threat processes comprise land conversion to agriculture and aquaculture, collection as biological resources, and residential and commercial development. The dominant drivers of extinction risk are the unscrupulous collection of live plants and seeds for horticultural trade and private ornamental collections, smallholder livestock ranching and smallholder annual agriculture. Our findings demonstrate that global species assessments are readily achievable for major groups of plants with relatively moderate resources, and highlight different conservation priorities and actions to those derived from species assessments of key animal groups.

8.
Elife ; 3: e00590, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24448405

RESUMO

The rapid expansion of human activities threatens ocean-wide biodiversity. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global marine extinction risk. We present the first systematic analysis of threat for a globally distributed lineage of 1,041 chondrichthyan fishes-sharks, rays, and chimaeras. We estimate that one-quarter are threatened according to IUCN Red List criteria due to overfishing (targeted and incidental). Large-bodied, shallow-water species are at greatest risk and five out of the seven most threatened families are rays. Overall chondrichthyan extinction risk is substantially higher than for most other vertebrates, and only one-third of species are considered safe. Population depletion has occurred throughout the world's ice-free waters, but is particularly prevalent in the Indo-Pacific Biodiversity Triangle and Mediterranean Sea. Improved management of fisheries and trade is urgently needed to avoid extinctions and promote population recovery. DOI: http://dx.doi.org/10.7554/eLife.00590.001.


Assuntos
Extinção Biológica , Tubarões/crescimento & desenvolvimento , Rajidae/crescimento & desenvolvimento , Animais , Conservação dos Recursos Naturais , Humanos , Oceanos e Mares , Medição de Risco
9.
Glob Ecol Biogeogr ; 23(1): 40-51, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26430385

RESUMO

AIM: Global-scale studies are required to identify broad-scale patterns in the distributions of species, to evaluate the processes that determine diversity and to determine how similar or different these patterns and processes are among different groups of freshwater species. Broad-scale patterns of spatial variation in species distribution are central to many fundamental questions in macroecology and conservation biology. We aimed to evaluate how congruent three commonly used metrics of diversity were among taxa for six groups of freshwater species. LOCATION: Global. METHODS: We compiled geographical range data on 7083 freshwater species of mammals, amphibians, reptiles, fishes, crabs and crayfish to evaluate how species richness, richness of threatened species and endemism are distributed across freshwater ecosystems. We evaluated how congruent these measures of diversity were among taxa at a global level for a grid cell size of just under 1°. RESULTS: We showed that although the risk of extinction faced by freshwater decapods is quite similar to that of freshwater vertebrates, there is a distinct lack of spatial congruence in geographical range between different taxonomic groups at this spatial scale, and a lack of congruence among three commonly used metrics of biodiversity. The risk of extinction for freshwater species was consistently higher than for their terrestrial counterparts. MAIN CONCLUSIONS: We demonstrate that broad-scale patterns of species richness, threatened-species richness and endemism lack congruence among the six freshwater taxonomic groups examined. Invertebrate species are seldom taken into account in conservation planning. Our study suggests that both the metric of biodiversity and the identity of the taxa on which conservation decisions are based require careful consideration. As geographical range information becomes available for further sets of species, further testing will be warranted into the extent to which geographical variation in the richness of these six freshwater groups reflects broader patterns of biodiversity in fresh water.

10.
Science ; 330(6010): 1503-9, 2010 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-20978281

RESUMO

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Vertebrados , Anfíbios , Animais , Aves , Espécies em Perigo de Extinção/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Extinção Biológica , Espécies Introduzidas , Mamíferos , Dinâmica Populacional
11.
Conserv Biol ; 21(3): 684-96, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17531047

RESUMO

As countries worldwide become increasingly interested in conserving biodiversity, the profile of national threatened species lists expands and these lists become more influential in determining conservation priorities. The World Conservation Union (IUCN) Categories and Criteria for evaluating extinction risk, originally intended for use at the global level, are increasingly being used at the national level. To facilitate this process, the IUCN recently published guidelines for the application of the criteria at subglobal levels. We evaluated the application of these guidelines, focusing on the opinions and experience of the global community of national assessors. To assess the extent to which IUCN criteria have been used in official national listing efforts, we sent a survey to 180 Convention on Biological Diversity national focal points designated by governments. Of the respondents, 77% had developed national threatened species lists. Of these, 78% applied a version of the IUCN criteria, and 88% plan to produce future threatened species lists. The majority of this last group (83%) will use IUCN criteria. Of the countries that have or will develop a threatened species list, 82% incorporated their list or the IUCN criteria into national conservation strategies. We further explored the issues highlighted by the survey results by integrating the experience of assessors that have produced national lists. Most of the problems national assessors faced when applying the IUCN criteria arose when the criteria were applied at the regional level without the IUCN Regional Guidelines and when assessors were confused about the purpose of the IUCN criteria and lacked training in their proper use. To improve their clarity and increase their repeatability, we recommend that the IUCN increase communication and information exchange among countries and between regional and global assessors, potentially through an interactive Web site, to facilitate the development of national red lists and to improve their conservation value within and between countries.


Assuntos
Animais Selvagens/classificação , Biodiversidade , Conservação dos Recursos Naturais , Animais , Coleta de Dados , Guias como Assunto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA