Story: Frogs

They don’t croak, and their dull browns and greens keep them well hidden among leaves and rocks. New Zealand’s frogs are unusual little creatures, and they need protecting. Once widespread, these ancient and primitive species are in decline, surviving in only a few locations.

Story by Paddy Ryan
Main image: Maud Island frog

Story summary

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Frogs

You would be very lucky to find a native frog. They are small and well camouflaged (most are brownish-green), and only come out at night.

Native frogs

There were once seven native species, but today only four survive, and in only a few places (none in the South Island):

  • Hochstetter’s frog. This is the most common species. It lives beside streams in the North Island.
  • Archey’s frog. It lives in only two areas: Coromandel and near Te Kūiti.
  • Hamilton’s frog. About 300 frogs live on Stephens Island in Cook Strait.
  • Maud Island frog. It is found only on Maud Island (over 10,000 frogs) and Motuara Island, in the Marlborough Sounds.

Features

New Zealand’s frogs belong to an ancient and primitive family, and do not exist anywhere else. They have evolved in unique ways. Their eyes are round, not slit, and they catch insects with their mouth, not a tongue. They have an extra vertebra, but no eardrums – and they don’t croak.

Habitat

Only Hochstetter’s frogs live near water. The other species keep damp in moist, shady places in the forest or amongst rocks. During the day they hide under logs, stones and bushes. Archey’s frogs can climb several metres up trees.

Mating and life cycle

Because they have no mating call, they find each other through smell and other signals.

Females lay their eggs under stones or leaves, and the males sit on the eggs till they hatch. Tadpoles grow inside the egg, and the young froglets hatch out almost fully formed. The frogs are long-lived – one survived for 29 years.

Threats and conservation

These frogs are threatened by animals and activities such as forest clearance and roadworks. They can also die from a fungus disease, so Auckland Zoo is breeding some in a safe zone. Some Maud Island frogs have been moved to Motuara Island to start a new group. It is illegal to harm the frogs or take them from their environment.

Frogs from Australia

Three species have been brought to New Zealand from Australia. Like most frogs, they have a loud call and a free-swimming tadpole stage.

  • Whistling frog. Brought to Greymouth in 1875, it has spread to other places. It makes a whistling ‘weeeep-eeeep-eeeep’ call and is mainly brown.
  • Green and golden bell frog. This arrived in the 1860s and lives in the upper North Island.
  • Southern bell frog. This lives throughout New Zealand, and is the largest species. It is mainly green, with a warty back.
How to cite this page:

Paddy Ryan, 'Frogs', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/en/frogs (accessed 19 March 2024)

Story by Paddy Ryan, published 24 September 2007