Global Amphibian Assessment

Key Findings on Threat Status and Distribution of All Amphibians Known to Science



Amphibians are a class of cold-blooded vertebrates that include frogs, toads, salamanders, newts, and caecilians. Most species in this class lay eggs and metamorphose from aquatic larvae to terrestrial adults, where they develop limbs and lungs. A few species do not undergo metamorphosis. Instead, they either develop directly from eggs without a larval stage or are viviparous, which means they give birth to live young without laying eggs.


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Nearly all species depend on moist environments to live and habitats with fresh water to breed. Tropical forests have the highest amphibian diversity, while temperate and arid regions generally have lower species richness. No amphibians are found in marine environments.

Global Amphibian Diversity

Source: Global Amphibian Assessment

Due to their high sensitivity to perturbations in the environment, amphibians are key indicators of the overall quality of a habitat. Of more than 6,000 species known to science, 168 species are believed to be extinct and at least 2,469 (43%) species are declining in population. The Global Amphibian Assessment (GAA) is a comprehensive study of the current threat status and distribution of all known species in the world. This project is a collaboration among scientists from IUCN-The World Conservation Union, Conservation International, and NatureServe, with contributions from over 600 amphibian experts in more than 60 countries.



1. To determine the extent of the current extinction crisis in amphibians, both in magnitude of threat and geographic location of the extinctions.

2. To identify geographic areas with the highest rates of extinction for conservation efforts.

3. To identify major factors that contribute to amphibian extinctions and develop prioritized conservation actions to address those threats.

4. To establish an expert network focused on amphibians and maintain updated information on the Global Amphibian Assessment so that expertise can be directed to the highest conservation priorities.



Global Distribution of Threatened Amphibians

Global distribution of threatened amphibians.

Source: Global Amphibian Assessment

Major Threats to Amphibians


Source: Global Amphibian Assessment 



The Amphibian Conservation Summit took place during September 17-19th, 2005 in Washington DC, where the IUCN/SSC Global Amphibian Specialist Group (GASG) and the GAA wrote an Amphibian Conservation Action Plan Declaration to reverse or reduce the decline of amphibians. The plan included some key actions to ameliorate amphibian declines:

1. Captive breeding for endangered species, which takes place in zoos.

2. Reintroduction programs to release amphibians to the wild in hope new populations will be established.

3. Exotic species removal when they threaten the existence of native species.

The above goals can be achieved by utilizing the following strategies outlined in the Amphibian Conservation Action Plan Declaration:




For more information on the Global Amphibian Assessment, please visit:

Additional information on amphibians can be found at: