Archey's frog (Leiopelma archeyi)
The frog-killer fungus Batrachochytrium dendrobatidis (or chytrid fungus) has resulted in the extinction of a number of frog species. It was feared that it would cause the extinction of New Zealand’s endemic frogs after it was detected in Archey’s frogs in the 1990’s. Despite a catastrophic decline in numbers in the Coromandel, the frogs survived infection at Whareorino (Waikato). The Coromandal population has now stabilised and it is estimated that 5,000 to 20,000 Archey’s frogs remain.
Archey’s frog is one of the world’s most primitive frogs, and is number one on the list of the top 100 EDGE amphibian species. EDGE stands for Evolutionary Distinct and Globally Endangered, and identifies the most unique of the earth’s biodiversity that is closest to extinction.
Hamilton's frog (Leiopelma hamiltoni)
Once classified as distinct species, the Maud Island frog race and the Stephen’s Island frog race are now known as one species with two Evolutionary Distinct Units.
There are only about 300 Stephen’s Island-race frogs. This makes it one of the rarest frogs in the world, and it is classified as Nationally Critical. Maintaining strict island biosecurity is paramount as the arrival of exotic pests or the frog-killer (chytrid) fungus could easily cause the extinction of the race. The Maud Island frogs are more abundant and classified as Nationally Vulnerable.