Conservation Projects > Kiwi Information and Statistics

Kiwi Information and Statistics

New Zealand Conservation Trust - Kiwis at Willowbank

Kiwi Breeding Area

The kiwi breeding area covers an outdoor open area of bush land, approximately 2 Hectares in size. This area has been extensively planted and is surrounded by a high predator-proof fence sunk deep into the ground. It is the home of several breeding pairs of kiwi. Rarely seen during the day, these birds are very active at night-time, and readily viewed under the lights. The juvenile kiwi can be viewed in a huge nocturnal house. At any one time there are 8 to 10 birds in this area. These are North Island Brown Kiwi that have been bred at Willowbank. Kiwi are naturally very shy and keep well hidden from humans but at Willowbank our kiwi are calm and relaxed.

Willowbank has bred North Island Brown Kiwi for many viewing facilities and for advocacy in New Zealand. Over the 2005 - 2006 season Willowbank has become involved in the South Island Operation Nest Egg Programme where eggs from Haast Tokoeka and Okarito Brown Kiwi are taken from the wild to hatch at the facility run by the New Zealand Conservation Trust based at Willowbank. It is expected over the next season that up to 60 eggs will be pulled from the wild to be incubated in this way as the predation in these areas is very difficult to control.

The Kiwi in New Zealand

The geographic isolation of the islands making up New Zealand means that 90% of New Zealand's flora and fauna is found nowhere else in the world (although some similarities can be found in South American forest life) and still flourish as they did 100 million years ago. Now New Zealand has only approximately 25% of its original (prior to human settlement) forest cover remaining. The Kiwi Kiwi birds are one of the world's oddities. They have many mammalian features such as two functioning ovaries, heavy bone marrow, cat like whiskers and hair like feathers, along with many unusual birdlike features. Kiwi lay the largest egg in proportion to their size of any species of bird at 20% of the females’ body weight. They have no wings, and almost one third of their total weight is made up from two heavily muscled legs. Their long bill allows deep probing into the ground for earthworms, and they have nostrils located on the tip of their bill, an adaptation that often requires a loud snort to clear.

Kiwi evolved for 70 million years before man introduced the many mammals that are found in this country now. Chick and eggs are very vulnerable to predators, which include possums, stoats, ferrets, feral cats, pigs and dogs. Also the removal of large areas of forest has reduced the habitat and left fragmented populations of kiwi across the country.

The male incubates the egg for 70 to 90 days. It can take four days for a kiwi chick to break out of its egg and by then it is exhausted. It is sustained with the yolk for up to a week and from then it must fend for itself. After hatching, it's a race against time to reach 1kg, when a chick is stronger and more likely to hold its own. This can take up to a year.
95% of these chicks will be predated during the first few weeks of their lives so most populations probably consist of aging birds. We will therefore see a rapid decline in population as these birds begin to die of old age.

The Kiwi population of 80 years ago was around 5 million birds. Today they have plummeted to 50,000 - 60,000. North Island Brown Kiwi North Island Brown kiwi are found in scattered populations throughout the North Island. There is a small range of colour for these kiwi, from russet red to almost black and the occasional albino.

South Island Kiwi South Island species and sub species are: Great spotted, Little Spotted, Okarito Brown (Rowi), Haast Tokoeka and Stewart Island Brown. Great Spotted Kiwi has dropped from 30,000 to approximately 10,000. Okarito Brown has dropped from 3000 to 200. Haast Tokoeka has dropped from 6000 to 200.

Recovery Work on Kiwi

The Kiwi Recovery Programme has been set up by the Department of Conservation to prevent the decline of kiwi numbers. In The Nest Egg Program' the eggs are removed from the wild, hatched and reared in captivity then released back into the wild when big enough to defend themselves against predators. 'Communities for Kiwis' scheme manages patches of kiwi habitat on private and public land. 'Kiwi Sanctuaries' Five sanctuaries have been created covering 43,000 hectares protecting the critically endangered Okarito Brown and Haast Tokoeka and some areas of North Island Brown kiwi.
In these areas DOC have used intensive ground based predator control to knock the number of possums, stoats and ferrets to as low as possible. In some areas 1080 aerial baits are being trialed to assess the effects compared to trapping.


© New Zealand Conservation Trust 2006 - 2010, 60 Hussey Rd, Harewood, Christchurch Phone: +64 3 359 6226, Fax: +64 3 359 6212, Email: info@nzconservationtrust.org.nz		Privacy \| Disclaimer \| Site Map website by digitise