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1.
Nature ; 605(7909): 285-290, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35477765

RESUMEN

Comprehensive assessments of species' extinction risks have documented the extinction crisis1 and underpinned strategies for reducing those risks2. Global assessments reveal that, among tetrapods, 40.7% of amphibians, 25.4% of mammals and 13.6% of birds are threatened with extinction3. Because global assessments have been lacking, reptiles have been omitted from conservation-prioritization analyses that encompass other tetrapods4-7. Reptiles are unusually diverse in arid regions, suggesting that they may have different conservation needs6. Here we provide a comprehensive extinction-risk assessment of reptiles and show that at least 1,829 out of 10,196 species (21.1%) are threatened-confirming a previous extrapolation8 and representing 15.6 billion years of phylogenetic diversity. Reptiles are threatened by the same major factors that threaten other tetrapods-agriculture, logging, urban development and invasive species-although the threat posed by climate change remains uncertain. Reptiles inhabiting forests, where these threats are strongest, are more threatened than those in arid habitats, contrary to our prediction. Birds, mammals and amphibians are unexpectedly good surrogates for the conservation of reptiles, although threatened reptiles with the smallest ranges tend to be isolated from other threatened tetrapods. Although some reptiles-including most species of crocodiles and turtles-require urgent, targeted action to prevent extinctions, efforts to protect other tetrapods, such as habitat preservation and control of trade and invasive species, will probably also benefit many reptiles.


Asunto(s)
Conservación de los Recursos Naturales , Extinción Biológica , Reptiles , Caimanes y Cocodrilos , Anfibios , Animales , Biodiversidad , Aves , Mamíferos , Filogenia , Reptiles/clasificación , Medición de Riesgo , Tortugas
2.
Conserv Biol ; 36(1): e13781, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34057250

RESUMEN

The COVID-19 pandemic has had an enormous impact on almost all aspects of human society and endeavor; the natural world and its conservation have not been spared. Through a process of expert consultation, we identified and categorized, into 19 themes and 70 subthemes, the ways in which biodiversity and its conservation have been or could be affected by the pandemic globally. Nearly 60% of the effects have been broadly negative. Subsequently, we created a compendium of all themes and subthemes, each with explanatory text, and in August 2020 a diverse group of experienced conservationists with expertise from across sectors and geographies assessed each subtheme for its likely impact on biodiversity conservation globally. The 9 subthemes ranked highest all have a negative impact. These were, in rank order, governments sidelining the environment during their economic recovery, reduced wildlife-based tourism income, increased habitat destruction, reduced government funding, increased plastic and other solid waste pollution, weakening of nature-friendly regulations and their enforcement, increased illegal harvest of wild animals, reduced philanthropy, and threats to survival of conservation organizations. In combination, these impacts present a worrying future of increased threats to biodiversity conservation but reduced capacity to counter them. The highest ranking positive impact, at 10, was the beneficial impact of wildlife-trade restrictions. More optimistically, among impacts ranked 11-20, 6 were positive and 4 were negative. We hope our assessment will draw attention to the impacts of the pandemic and, thus, improve the conservation community's ability to respond to such threats in the future.


La pandemia de COVID-19 ha tenido un impacto enorme sobre casi todos los aspectos de la sociedad humana y sus proyectos; el mundo natural y su conservación no han sido la excepción. Por medio de un proceso de consultas a expertos, identificamos y categorizamos en 19 temas y 70 subtemas las maneras en las que la biodiversidad y su conservación han sido o podrían ser afectadas mundialmente por la pandemia. Casi el 60% de los efectos han sido claramente negativos. Posteriormente, creamos un compendio de todos los temas y subtemas, cada uno con textos explicativos, para que en agosto de 2020 un grupo diverso de conservacionistas experimentados con conocimiento de todos los sectores y geografías evaluara cada subtema de acuerdo con su probabilidad de impactar sobre la conservación de la biodiversidad en todo el mundo. Los nueve subtemas con la clasificación más alta tienen un impacto negativo. Estos temas son, en orden de clasificación: los gobiernos dejando de lado al ambiente durante su recuperación económica, reducción de los ingresos basados en el turismo de fauna, incremento en la destrucción de hábitat, financiamiento reducido del gobierno, aumento de la contaminación por plásticos y otros desechos sólidos, debilitamiento de las regulaciones en pro de la naturaleza y su aplicación, incremento en la captura ilegal de animales, disminución de la filantropía y amenazas para la supervivencia de las organizaciones de conservación. La combinación de estos impactos representa un futuro preocupante lleno de amenazas para la conservación de la biodiversidad y una capacidad reducida para contrarrestarlas. El impacto positivo con la clasificación más alta, el 10, fue el impacto benéfico de las restricciones en el mercado de fauna. De manera más optimista, entre los impactos clasificados de los lugares del 11 al 20, seis fueron positivos y cuatro fueron negativos. Esperamos que nuestra evaluación enfoque la atención hacia los impactos de la pandemia y así mejore la habilidad de la comunidad conservacionista para responder a tales amenazas en el futuro. Importancia Relativa de los Impactos de la Pandemia de COVID-19 sobre la Conservación Mundial de la Biodiversidad.


Asunto(s)
COVID-19 , Pandemias , Animales , Biodiversidad , COVID-19/epidemiología , Conservación de los Recursos Naturales , Humanos , SARS-CoV-2
3.
J Anim Ecol ; 84(1): 113-23, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24942147

RESUMEN

Undersampling is commonplace in biodiversity surveys of species-rich tropical assemblages in which rare taxa abound, with possible repercussions for our ability to implement surveys and monitoring programmes in a cost-effective way. We investigated the consequences of information loss due to species undersampling (missing subsets of species from the full species pool) in tropical bat surveys for the emerging patterns of species richness (SR) and compositional variation across sites. For 27 bat assemblage data sets from across the tropics, we used correlations between original data sets and subsets with different numbers of species deleted either at random, or according to their rarity in the assemblage, to assess to what extent patterns in SR and composition in data subsets are congruent with those in the initial data set. We then examined to what degree high sample representativeness (r ≥ 0·8) was influenced by biogeographic region, sampling method, sampling effort or structural assemblage characteristics. For SR, correlations between random subsets and original data sets were strong (r ≥ 0·8) with moderate (ca. 20%) species loss. Bias associated with information loss was greater for species composition; on average ca. 90% of species in random subsets had to be retained to adequately capture among-site variation. For nonrandom subsets, removing only the rarest species (on average c. 10% of the full data set) yielded strong correlations (r > 0·95) for both SR and composition. Eliminating greater proportions of rare species resulted in weaker correlations and large variation in the magnitude of observed correlations among data sets. Species subsets that comprised ca. 85% of the original set can be considered reliable surrogates, capable of adequately revealing patterns of SR and temporal or spatial turnover in many tropical bat assemblages. Our analyses thus demonstrate the potential as well as limitations for reducing survey effort and streamlining sampling protocols, and consequently for increasing the cost-effectiveness in tropical bat surveys or monitoring programmes. The dependence of the performance of species subsets on structural assemblage characteristics (total assemblage abundance, proportion of rare species), however, underscores the importance of adaptive monitoring schemes and of establishing surrogate performance on a site by site basis based on pilot surveys.


Asunto(s)
Biodiversidad , Quirópteros/fisiología , Conservación de los Recursos Naturales/métodos , Animales , Clima Tropical
4.
Nat Ecol Evol ; 7(8): 1211-1220, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37414949

RESUMEN

Overexploitation is a major threat to biodiversity and international trade in many species is regulated through the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). However, there is no established method to systematically determine which species are most at risk from international trade to inform potential trade measures under CITES. Here, we develop a mechanism using the International Union for Conservation of Nature's Red List of Threatened Species to identify species that are likely to be threatened by international trade. Of 2,211 such species, CITES includes 59% (1,307 species), leaving two-fifths overlooked and in potential need of international trade regulation. Our results can inform deliberations on potential proposals to revise trade measures for species at CITES Conference of the Parties meetings. We also show that, for taxa with biological resource use documented as a threat, the number of species threatened by local and national use is four times greater than species likely threatened by international trade. To effectively address the overexploitation of species, interventions focused on achieving sustainability in international trade need to be complemented by commensurate measures to ensure that local and national use and trade of wildlife is well-regulated and sustainable.


Asunto(s)
Comercio , Conservación de los Recursos Naturales , Animales , Conservación de los Recursos Naturales/métodos , Internacionalidad , Especies en Peligro de Extinción , Animales Salvajes
7.
PLoS One ; 9(8): e100173, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25111137

RESUMEN

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.


Asunto(s)
Conservación de los Recursos Naturales , Extinción Biológica , Reptiles , Animales , Especies en Peligro de Extinción/estadística & datos numéricos , Madagascar , Reptiles/clasificación , Riesgo , Análisis Espacial
8.
Zookeys ; (81): 51-71, 2011 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-21594161

RESUMEN

We describe a new mantellid frog of the subfamily Mantellinae from the karstic Bemaraha Plateau, western Madagascar. The new species belongs to the genus Gephyromantis, subgenus Phylacomantis, which previously included Gephyromantis azzurrae, Gephyromantis corvus and Gephyromantis pseudoasper. Gephyromantis atsingysp. n. has a snout-vent length of 35-43 mm and is a scansorial frog living among the Tsingy de Bemaraha pinnacles and inside the caves present in the area. A morphological analysis and biomolecular comparison revealed the degree of differentiation between these four species of the Phylacomantis subgenus.The new species seems to be endemic to Tsingy de Bemaraha.

9.
PLoS One ; 6(12): e27570, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22194787

RESUMEN

Understanding the patterns of wild meat consumption from tropical forests is important for designing approaches to address this major threat to biodiversity and mitigate potential pathways for transmission of emerging diseases. Bushmeat consumption has been particularly poorly studied in Madagascar, one of the world's hottest biodiversity hotspots. Studying bushmeat consumption is challenging as many species are protected and researchers must consider the incentives faced by informants. Using interviews with 1154 households in 12 communes in eastern Madagascar, as well as local monitoring data, we investigated the importance of socio-economic variables, taste preference and traditional taboos on consumption of 50 wild and domestic species. The majority of meals contain no animal protein. However, respondents consume a wide range of wild species and 95% of respondents have eaten at least one protected species (and nearly 45% have eaten more than 10). The rural/urban divide and wealth are important predictors of bushmeat consumption, but the magnitude and direction of the effect varies between species. Bushmeat species are not preferred and are considered inferior to fish and domestic animals. Taboos have provided protection to some species, particularly the Endangered Indri, but we present evidence that this taboo is rapidly eroding. By considering a variety of potential influences on consumption in a single study we have improved understanding of who is eating bushmeat and why. Evidence that bushmeat species are not generally preferred meats suggest that projects which increase the availability of domestic meat and fish may have success at reducing demand. We also suggest that enforcement of existing wildlife and firearm laws should be a priority, particularly in areas undergoing rapid social change. The issue of hunting as an important threat to biodiversity in Madagascar is only now being fully recognised. Urgent action is required to ensure that heavily hunted species are adequately protected.


Asunto(s)
Especies en Peligro de Extinción/estadística & datos numéricos , Conducta Alimentaria , Carne/estadística & datos numéricos , Animales , Animales Salvajes , Preferencias Alimentarias , Madagascar , Recuerdo Mental , Modelos Biológicos , Especificidad de la Especie
10.
Ecohealth ; 7(2): 248-51, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20517634

RESUMEN

Chytridiomycosis (Bd) is contributing to amphibian extinctions worldwide but has so far not been detected in Madagascar. The high likelihood for Bd to spread to the island and efface this amphibian diversity and endemism hotspot requires respective conservation policies to be developed. Bd could be introduced by the large number of tourists that visit protected areas; therefore, increasing awareness among tourists and encouraging them to participate in safety measures should be a priority conservation action. However, concerns have been raised that tourists would not be able to distinguish between an amphibian disease harmless to humans and emerging diseases that would imply a danger for human health, invoking a negative image of Madagascar as an ecotourism destination. We evaluated whether informing tourists about this infectious animal disease would cause health scare and diminish trip satisfaction. Based on 659 respondents we found that most ecotourists favored to be informed about Bd and were proactive about participating in prevention measures, refuting previous concerns.


Asunto(s)
Quitridiomicetos , Conocimientos, Actitudes y Práctica en Salud , Micosis/prevención & control , Micosis/psicología , Viaje , Anfibios/microbiología , Animales , Conservación de los Recursos Naturales , Ecología , Educación en Salud/métodos , Humanos , Madagascar , Micosis/transmisión , Encuestas y Cuestionarios
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