Date: 23 August 2018 Source: Office of the Minister of Conservation
Conservation Minister Eugenie Sage said New Zealand’s three native frog species are different to frogs anywhere else in the world.
“New Zealand’s frogs have barely changed in 70 million years. They don’t croak like most frogs, they hatch as ‘froglets’ – almost fully formed frogs – rather than tadpoles, and their pupils are round rather than slit-shaped. The male Archey’s frog carries his offspring on his back.
“As with other native species, predators and habitat loss are threatening frogs with extinction. Current conservation efforts are helping these unique species. While the status of two frogs has improved, these improvements reflect better information rather than a noticeable improvement in numbers.
“Our frogs are just hanging on, there’s no doubt they’re still in grave danger.”
Eleven Hochstetter’s frog populations previously assessed separately have been combined into a single assessment for the report following new research that indicates their genetic distinctiveness is not sufficient to consider them as separate species.
Despite the merger Hochstetter’s frog is still classified as At Risk – Declining, reflecting the ongoing decline that is anticipated across all Hochstetter’s frog populations.
Archey’s frog has an improved status from Threatened – Nationally Vulnerable to At Risk – Declining. This change is due to a better understanding of likely population trends rather than observed increases in their populations.
Hamilton’s frog has changed from Threatened – Nationally Critical to Threatened – Nationally Vulnerable due to new genetic research indicating that two frog populations on different islands and previously considered as separate species are actually one species.
This report replaces the New Zealand Threat Classification System report on native frogs 2013.
Hamilton's frog survives as original populations only on Takapourewa/Stephen’s Island in Cook Strait and Te Pākeka/Maud Island in the Marlborough Sounds, where it is carefully managed by DOC. Fossil records show it was once spread from Waikato to Punakaiki. It lives away from water on the forest floor, and is the largest native frog growing up to 51 mm long.
DOC has established populations on other islands as insurance against a disaster, such as a fire or pest incursion wiping out the remaining populations.
Hochstetter's frog is the most widespread native frog and occurs in the upper half of the North Island, including at Waipu, Aotea/Great Barrier Island, Coromandel, and the Raukumara Ranges. It is the most aquatic of the native frogs (living beside streams), is generally dark brown, grows up to 48 mm long, has partially webbed feet and has more warts than the other native frogs.
Archey’s frogs are modern-day dinosaurs, almost unchanged from their 150 million-year old fossilised relatives. Archey's frog is internationally important and is the number one Evolutionarily Distinct and Globally Endangered (EDGE) amphibian species. It is our smallest native frog, growing up to 37 mm long, and like Hamilton’s frog it lives away from water on the forest floor. It is found in Coromandel Peninsula and Whareorino Forest.