Raising the profile of amphibians

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As part of our 10 year anniversary celebrations of ZSL’s EDGE of Existence Programme, EDGE Fellow Alejandro Calzada explains how he’s working to safeguard the future of the granular salamander.  

Granular salamander
The granular salamander is Critically Endangered in the wild
 There are more than 7,650 species of amphibians currently known, and even more are described each year. But, amphibians are facing threats – such as habitat loss, climate change and disease – and populations worldwide are disappearing.

Through the ZSL EDGE of Existence Programme, we’re working to conserve our most unique and threatened amphibians, including toads that give birth through the skin of their backs, legless creatures that burrow through soil, and blind cave salamanders that can survive for a decade or more without food! In fact, there are currently 972 EDGE amphibians, which is more than any other EDGE group. 

Mexico is home to nine of the top 20 EDGE amphibians, and one of these amazing species is the granular salamander. Its name comes from its corrugated or granular skin, especially along the tail, and it’s known only from a small area in Toluca city, in the central State of Mexico. 

Belonging to the ‘mole salamander’ family, which diverged from all other salamanders over 140 million years ago, it’s very special as it’s highly evolutionarily distinct. Like many of its close relatives, it’s a metamorphosing species, which means that it has two different physical forms: a juvenile form that has external gills and lives underwater, and an adult form that lives on land. 

At the end of its juvenile stage, the granular salamander becomes an adult by losing its gills and fins, and replaces these features with eyelids and lungs, moving out of the water and making its home on land and returning to water only to breed. 

Sadly though, the granular salamander is Critically Endangered in the wild, and a major threat is introduced predatory fish. Added to the problem of habitat clearance and degradation as a result of extensive urban and agricultural expansion, it spells disaster for the EDGE species. 

Even though it is under special protection by the Government of Mexico, the granular salamander does not occur in any protected areas, so the conservation and restoration of its remaining habitat is an urgent priority in order to prevent its extinction in the wild. 

Through the EDGE Fellowship Programme, I’m working to determine the conservation priorities for the species by investigating the current distribution, range and population size of granular salamanders. The aim is to use this information as part of a future conservation strategy.  

My EDGE Fellowship will provide me with skills and expertise for conservation, and I’ve really enjoyed the opportunity to meet great people who are experienced in the conservation of different, interesting animals.


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