Our native frogs are small, nocturnal, and are hard to see as they camouflage themselves well. Three of our remaining species live on land in shady, moist forested areas, and one is semi-aquatic, living on stream edges.
Features of our native frogs
Maud Island frog on lichen, Maud Island
New Zealand's native frogs have several distinctive features, which make them very different from frogs elsewhere in the world:
- They have no external eardrum.
- They have round (not slit) eyes.
- They don't croak regularly like most frogs.
- They don't have a tadpole stage. The embryo develops inside an egg, and then hatches as an almost fully-formed frog. The young of most species are cared for by their parents - for example, the male Archey's frog may carry his young offspring around on his back.
New Zealand originally had seven species of native frog. Three species have become extinct since the arrival of humans and animal pests, like rats, in New Zealand. The four remaining species are:
The most widespread, the Hochstetter's frog has been sighted around the upper half of the North Island, including at Waipu, Great Barrier Island, the Coromandel, central North Island, and the Raukumara Ranges.
It is generally dark brown, grows up to 48mm long, has partially webbed feet and has more warts than the other native frogs.
Archey's frog are only found in the Coromandel and in one site west of Te Kuiti. It is the smallest native frog, growing up to 37mm long. They live in misty, moist areas around 400m in altitude.
One of the world's most endangered frogs, the Hamilton's frog is only found on Stephens Island in the Cook Strait.
Maud Island frog
This frog is only found on Maud Island in the Marlborough Sounds. DOC recently transferred some Maud Island frogs to Motuara Island.
There are also three introduced species of frog in New Zealand. These species are easily distinguished from native frogs because they have loud mating calls and pass through a tadpole stage.
Find out more about how to identify these introduced species.
Threats to frogs
Frogs are vulnerable to predators such as rats
Frogs are declining everywhere in the world. More than most creatures, frogs are sensitive to disease, pollution, chemical poisons and environmental changes, as they absorb many things through their sensitive skin.
Fossil records show that our native frogs were spread throughout both the North and South Islands several thousand years ago. The four remaining species have declined significantly in range and in numbers over the past one to two thousand years, as land has been cleared of forest and predators have been introduced.
Hamilton's frog is the most critically endangered species, with less than 300 individuals remaining. Fossil records show it was once spread from Waikato to Punakaiki. Now it survives only on Stephens Island, where it is carefully managed by the Department of Conservation.
DOC has created a second population of the frogs on the island, enclosed in a predator-proof fence because tuatara occasionally eat frogs.
Frogs are vulnerable to introduced predators such as rats and cats. In late 1999, a sighting of the aggressive Eastern banjo frog in Auckland also raised fears that if this alien invader gets a foothold, it will out-compete native frogs in their habitat.
DOC's work with native frogs
Maud Island frog study area - showing board walk and the shelter used for weighing and measuring frogs
DOC has a Native Frog Recovery Group that coordinates management and research into native frogs to help with their conservation.
The impact of 1080 on native frogs has been investigated, and methods for frog monitoring and translocation are being developed and improved. Frog distribution and their numbers are also being documented.
In 1997 300 Maud Island frogs were transferred to Motuara Island - the first-ever inter-island translocation of a native frog. To date, this transfer has been successful.
Establishing a second population of the frog in another location is insurance against a disaster, such as fire, wiping out a sole surviving population. A separate population of Hamilton's frog has also been established on its home on Stephens Island and is monitored closely by DOC staff.
DOC is also using an innovative new method – a photo stage – to identify individual Archey's frogs. A highly endangered species, identifying individuals allows us to monitor the frogs and better understand what factors are leading to the species' decline.
Read more about the photo stage.
You can help
As native frogs are small, well-camouflaged and nocturnal, they are hard to find.
The public can assist DOC greatly by reporting any sightings of native (and introduced) frogs.
Record carefully the location, the type of habitat (stream edge, forest floor), the time and date you sighted them, and if possible take photographs. Avoid touching the frogs, because you may damage their sensitive skin. If you do touch them, make sure your hands are wet.
DOC is also interested in records of introduced frogs as populations may transmit disease, or directly compete or predate native frogs. Take a look at our simple to use introduced frog identification keyto find out what species you have found.