Zoo: Mining threat to 'living fossil' frog

London Zoo is urging people to help Archey's frogs by opposing NZ mining plans. Photo / Supplied

Mining in the Coromandel could push the world's most endangered species of frog to extinction, experts at Auckland Zoo have warned.

Zookeepers say they tried without success for six years to breed Archey's frog in captivity, so there is no back-up population if the amphibians die out.

At 37mm long, Archey's frogs are the smallest of New Zealand's four remaining native frogs and are said to be almost identical to frogs that lived with the dinosaurs 150 million years ago.

Their one remaining stronghold is the moist, misty areas of the Coromandel Peninsula. They also live in a smaller site west of Te Kuiti.

In a submission opposing Government proposals to open protected areas to mining, Auckland Zoo said mining protected parts of the Coromandel could drive Archey's frogs to extinction.

Another native frog, the Hochstetter's, could severely decline.

The submission said mining any of the land the Government proposed taking out of Schedule Four of the Crown Minerals Act, which prohibits mining in national parks and other high-value conservation land, would endanger forests, waterways, and wildlife including brown teal, kereru, kaka and kiwi.

International frog expert Dr Phil Bishop, of Otago University, said the areas the Government had suggested opening to mining included several of the best long-term frog monitoring sites anywhere in the world.

"This proposed mining activity, which ironically comes during the Year of International Biodiversity, could cause the extinction of Archey's frog, and a severe decline in the Hochstetter's frog population - a devastating blow to global amphibian conservation.

"Archey's frog is listed by the Zoological Society of London as the world's most evolutionarily distinct and globally endangered amphibian out of 6000 species. New Zealand has an obligation to do everything it can to ensure the survival of these incredible amphibians," said Dr Bishop.

New Zealand is thought to have lost about 88 per cent of its Archey's frogs since 1996, although no one is sure how many are left.

Efforts to save the species by breeding them at Auckland Zoo failed because researchers had struggled to keep them healthy.

Out of 83 Archey's frogs kept at Auckland Zoo since March 2005, 42 had died, it was reported last year. The frogs had been kept inside to protect them from chytrid fungus, which has wiped out some Australian frog species and has started killing New Zealand frogs.

Some ecologists consider frogs the "canaries in the goldmine" of environmental decline because their porous skin makes them sensitive to changes.

London Zoo is urging Britons to make submissions opposing the New Zealand mining proposals.

The Zoological Society of London website described Archey's frogs as a "living fossil" and the "most evolutionarily distinct and globally endangered amphibian on the planet."

Submissions on the Government's discussion paper about mining on the conservation estate close at 5pm tomorrow.