Article

Annual temperature data for two Malagasy sites of high anuran diversity

45:85-94.

ABSTRACT Times Cited: 0

0 Bookmarks
 · 
63 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT:  We assessed the extinction risks of Malagasy amphibians by evaluating their distribution, occurrence in protected areas, population trends, habitat quality, and prevalence in commercial trade. We estimated and mapped the distribution of each of the 220 described Malagasy species and applied, for the first time, the IUCN Red List categories and criteria to all species described at the time of the assessment. Nine species were categorized as critically endangered, 21 as endangered, and 25 as vulnerable. The most threatened species occur on the High Plateau and/or have been subjected to overcollection for the pet trade, but restricted extent of occurrence and ongoing habitat destruction were identified as the most important factors influencing extinction threats. The two areas with the majority of threatened species were the northern Tsaratanana-Marojejy-Masoala highlands and the southeastern Anosy Mountains. The current system of protected areas includes 82% of the threatened amphibian species. Of the critically endangered species, 6 did not occur in any protected area. For conservation of these species we recommend the creation of a reserve for the species of the Mantella aurantiaca group, the inclusion of two Scaphiophryne species in the Convention on the International Trade in Endangered Species Appendix II, and the suspension of commercial collecting for Mantella cowani. Field surveys during the last 15 years reveal no pervasive extinction of Malagasy amphibians resulting from disease or other agents, as has been reported in some other areas of the world.Resumen: Evaluamos los riesgos de extinción de anfibios malgaches mediante el análisis de su distribución, ocurrencia en áreas protegidas, tendencias poblacionales, calidad del hábitat y prevalencia en el comercio. Estimamos y mapeamos la distribución de cada una de las 220 especies descritas para Madagascar y aplicamos, por primera vez, las categorías y criterios de la Lista Roja de IUCN a todas las especies descritas al momento de la evaluación. Nueve especies fueron clasificadas en peligro crítico, 21 como amenazadas y 25 como vulnerables. Las especies más amenazadas ocurren en High Plateau y/o han sido sujetas a sobreexplotación para el comercio de mascotas, pero identificamos a la extensión restringida de ocurrencia y a la destrucción del hábitat como los factores que más influyen sobre las amenazas de extinción. Las mesetas de Tsaratanana-Marojejy-Masoala en el norte y las Montañas Anosy en el sureste fueron las dos áreas con la mayoría de especies amenazadas. El actual sistema de áreas protegidas incluye a 82% de las especies de anfibios amenazadas. De las especies en peligro crítico, 6 no ocurrieron en ninguna área protegida. Para la conservación de estas especies recomendamos la creación de una reserva para especies del grupo de Mantella aurantiaca, la inclusión de dos especies de Scaphiophryne en el Apéndice II de la Convención Internacional para el Comercio de Especies en Peligro y la suspensión de la colecta comercial de Mantella cowani. Los estudios de campo llevados a cabo en los últimos 15 años no muestran la extinción generalizada de anfibios malgaches debido a enfermedades u otros agentes, como se ha registrado en algunas otras partes del mundo.
    Conservation Biology 11/2005; 19(6):1790 - 1802. · 4.36 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Amphibians are characterized both by a strongly increasing number of newly discovered species and by a high degree of decline. The observed increase in species numbers, over 25 percent in 11 years, is largely due to the intensified exploration of tropical areas and the application of more efficient techniques such as bioacoustics and molecular genetics, rather than to the elevation of subspecies to species rank or the distinction of species that were formerly considered synonymous. In the mantellid frogs of Madagascar, the many species newly described between 1992 and 2004 were as genetically divergent as those described in previous research periods, and most had not been collected previously, corroborating the lack of “taxonomic inflation” in this vertebrate class. Taxonomic exploration is still desperately needed to avoid misinterpretations in global conservation policy.
    BioScience 01/2005; 55(8):693-696. · 5.44 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: As the Earth warms, many species are likely to disappear, often because of changing disease dynamics. Here we show that a recent mass extinction associated with pathogen outbreaks is tied to global warming. Seventeen years ago, in the mountains of Costa Rica, the Monteverde harlequin frog (Atelopus sp.) vanished along with the golden toad (Bufo periglenes). An estimated 67% of the 110 or so species of Atelopus, which are endemic to the American tropics, have met the same fate, and a pathogenic chytrid fungus (Batrachochytrium dendrobatidis) is implicated. Analysing the timing of losses in relation to changes in sea surface and air temperatures, we conclude with 'very high confidence' (> 99%, following the Intergovernmental Panel on Climate Change, IPCC) that large-scale warming is a key factor in the disappearances. We propose that temperatures at many highland localities are shifting towards the growth optimum of Batrachochytrium, thus encouraging outbreaks. With climate change promoting infectious disease and eroding biodiversity, the urgency of reducing greenhouse-gas concentrations is now undeniable.
    Nature 01/2006; 439(7073):161-7. · 38.60 Impact Factor

Full-text

View
24 Downloads
Available from
Jun 5, 2014