Eleven hitherto unknown-about New Zealand frogs have been found surviving in a fragile, rocky area of mountains in the middle of New Zealand’s North Island.
This first new find of the threatened Hochstetter’s frog in a decade was made on Maungatautari, a mountain in the middle of the North Island of New Zealand.
The Maungatautari Ecological Island Trust, which is working to restore much of the mountain to its natural state, had hoped to reintroduce Hochstetter’s to the mountain, but by chance, a researcher surveying for insects found a male Hochstetter’s frog. The site was immediately surveyed and another ten, including young frogs that would have hatched this year, were found.
“This is the first confirmed population of Hochstetter’s on the mountain,” says Avi Holzapfel, the head of the frog recovery programme run by New Zealand’s conservation agency, the Department of Conservation. “Finding these frogs just by chance really in a habitat that is not considered prime habitat for Hochstetter’s at all… it’s a huge gift.”
Hochstetter’s, which are only 48 millimetres long, about the length of a female adult little finger, are well camouflaged and nocturnal in nature so they are particularly hard to find.
According to Dr Holzapfel the Hochstetter’s on Maungatautari are likely to be a distinct population, due to their long isolation from other groups of Hochstetter’s. Results from genetic testing should confirm this early 2005.
New Zealand native frogs are one of the most ancient lineages of frogs still alive in the world; they are so old that they were hopping around the feet of dinosaurs. They are, like the tuatara, relics from New Zealand’s Gondwanaland past.
Originally there were seven species of native frog in New Zealand, now there are only four. The four known species of New Zealand frogs —Hochstetter’s, the Archey’s frog, Hamilton’s frog and the Maud Island frog — lack external ears, don’t croak, are nocturnal and hatch directly into froglets without going through a tadpole stage.
Hochstetter’s are not the most endangered of New Zealand frogs — that distinction belongs to the Hamilton’s frog, which up until earlier this year lived only on one island off the coast of the South Island of New Zealand, Stephens Island. (A new colony has since been set up on a predator-free island in the same area.)
Dr Holzapfel believes that the Hochstetter’s frog probably numbers in the tens of thousands but like all the frogs endemic to New Zealand they are suffering from a decline in their habitat.
The Maungatautari Ecological Island Trust hopes to restore at least one part of New Zealand for such rare native species. The restoration plan involves encircling 3400 hectares of bush with a pest-proof fence and bringing back species that once lived there such as the kiwi, kokako, kakariki, tuatara and kaka.
So far funding of $4.5million has been raised enabling a pest-proof fence to be erected around two enclosures as examples of the whole project.
“The race is now on to erect the pest-proof fence around the whole mountain and protect these threatened frogs and any other species that may be surviving in small numbers,” says Jim Mylchreest, chief executive of the Maungatautari trust.