Climate change accelerates the extinction process in Madagascar

The new study, carried out by the American Museum of Natural History, provides the first details that show global warming forces species to migrate to tropical mountains when their habitat they move up.

Chistopher Raxworthy - deputy head of the Department of Reptiles - predicts that at least three species of amphibians and reptiles in the mountains of northern Madagascar will be extinct by 2050 to 2100 due to loss of habitat related to warming. Global. They now have to move to the upper slopes due to the loss of habitat in the highlands compared to the warmer sea level, but then they will have nowhere to migrate.

Raxworthy said: 'Localized distribution is high near the highest peaks along with a wide-angle upward shift due to the effect of rising temperatures as a harmful combination leading to the extinction process' . In a new article published in Global Change Biology, Raxworthy and his colleagues found the general trend of environmental elevation change in 30 amphibian and reptilian species.

The phenomenon of upward migration is a predictable reaction to increasing temperature. Other studies, including the study of J. Alan Pounds in Costa Rica, have provided some empirical evidence on how tropical species respond to climate change. However, Raxworth's research excelled by the number and diversity of species, meteorological changes in the same period of time, the conversion of elevation on a relatively large scale as well as an overview of the possibilities. extinction of tropical mountain populations. There is still scarcity of information on climate impacts on biodiversity in the tropics.

Calumma tsaratananensis - endemic species representing the habitat at the top of Tsaratanana.(Photo: AMNH)

Raxworthy has been investigating the diversity of reptile groups in Madagascar since 1985. He discovered that most of the upward migration process happened casually . In a repeat survey taking place in the mountains of northern Madagascar - Mount Tsaratanana, he found that some species have disappeared from places where they often appear before. Moreover, some of them appear in the next higher area. Raxworthy explained: 'I find this very strange, but then I sit down, review the data, and see that trend is quite popular'. He selected high-altitude records and compared surveys over a period of over ten years.

The results were unexpected. Of the 30 species of geckos, short-legged lizards, chameleon, and frogs, there is a pattern of upward migration with an average height of 19 to 51 meters (62 to 167 fit) in a decade. by. When comparing results with meteorological records as well as simulating climate change, animal movement may be related to an increase in temperature from 0.1 ° C to 0.37 ° C (from 0.18 ° F to 0.67 ° F) also in that decade, equivalent to the projected upward movement of between 17 and 74 meters (59 to 243 feet).

Raxworthy's research results are accurate because there are species diversity in the analysis process. A collection of animals of 5 different amphibian and reptilian families, such as toad small mouths, Mantella frogs, chameleon, geckos and short-legged lizards, makes the hypothesis of the post-hoc change of inexplicable Get this trend up. Raxworthy said: 'When you see a general trend in all these groups of organisms, it must be related with a general explanation as the heat rises, not things that are hard to perceive as transformations. seasonal'.

The direct link between observed mountain movement, extinction as well as climate change has certain consequences for the national park network in Madagascar. The Madagascar government currently plans to reserve 10% of its land for conservation purposes. Previous research conducted by Raxworthy and colleagues, published in the April issue of Science, was based on the distribution of 2,300 animals to map the island nation to provide enough habitat for all species. .

'The Malagasy government is building more new protected areas as well as conducting forest protection. However, sadly with a phenomenon like global warming, species will turn to higher habitats. Therefore they can still lose their habitat leading to extinction. This conservation issue therefore requires a global solution. '

The research was funded by the National Science Foundation. Raxworthy collaborated with scientists at Antananarivo University in Madagascar, Chung-Hsing National University in Taiwan, Michigan University, and Oxford University in England.

Reference article:

Raxworthy et al. Đang exfoliate, vulnerability của kết thúc của tropical tropical Global Change Biology, 2008; 0 (0): 080506181133486 DOI: 10.1111 / j.1365-2486.2008.01596.x