EDGE will conduct urgent field surveys for the 20 Mexican lungless salamander species on the EDGE Amphibian top 100 list, half of which are feared to be extinct.
The lungless salamanders (or Plethodontidae) constitute the largest and most diverse salamander family. They diverged from all other amphibian lineages 145 million years ago when dinosaurs were still dominant. This is equivalent to the evolutionary time separating wombats from whales. They do not possess lungs and breathe entirely through their skin and the lining of their mouth. They are small, often dark or earthy coloured species that may be found on the ground or hiding in vegetation growing on trees. Their reproduction is independent of water – their eggs are laid in concealed damp locations on the land and hatch into miniature adults that bypass the external larval phase. They are poorly understood creatures that, in many cases, seem to be disappearing without a trace in the wild.
One fifth of the top 100 EDGE amphibians are lungless salamanders from Mexico. Of these 20 species, half are considered to be possibly extinct and some have not been seen for over two decades. They are being adversely affected by habitat destruction in the majority of cases, as logging, agriculture and human settlement remove suitable habitat from their often tiny ranges. Some species have undergone rapid enigmatic declines of late which may be caused by volcanic activity, climate change or the fungal disease chytridiomycosis. As a result, all but one are classified as Critically Endangered on the IUCN Red List of Threatened Species (the exception being Townsend's dwarf salamander which is listed as Endangered).
EDGE aims to carry out urgent field survey work to determine which of the EDGE top 100 lungless salamander species in Mexico still survive in the wild. We will assess the current status and distribution of these species to identify threats, and gather other information required to protect the surviving species, including monitoring for chytrid. All information collected will feed into the formulation of a Conservation Action Plan for the most endangered Mexican lungless salamanders. We hope to create a network of Mexican stakeholders, from conservation organisations to local community members that is informed about the plight of these species and supported to reverse the trends threatening to render so many of these salamanders extinct.