Decline and predation
In the early 1900s the kōkako was common in forests throughout New Zealand.
South Island kōkako are now assumed to be extinct. However it's remotely possible they may survive in low numbers in remote parts of the South Island and Stewart Island. Currently there are no confirmed reports of surviving South Island kōkako.
For the North Island kōkako, there has been a significant decline over the last 20 years. Management is reversing that trend in many areas to the point that the kokako has been reclassified from Threatened to At Risk: Recovering.
Predation at nests – mainly by ship rats and possums, and occasionally stoats – is the primary cause of North Island kōkako declines. Female kōkako are particularly at risk of predation as they do all the incubation and brooding throughout a 50-day nesting period. Years of such predation have resulted in populations that are predominantly male and with consequent low productivity rates.
Four day old North Island kōkako chick
Kōkako project in the Hunua Ranges
In the mid 1990s DOC and the Auckland Regional Council started a joint project to protect the population of 21 North Island kōkako in the Hunua Ranges.
In 1994 the only remaining breeding female in Hunua fledged 3 chicks, heralding a new era of recovery. The population has grown slowly with the protection of nests from predators and close monitoring of nesting birds.
This population has also been helped by translocating kōkako from elsewhere (Mapara, Pureora, Tiritiri Matangi) to boost the population numbers and genetic diversity. A census in 2015 found 55 kokako pairs!
DOC's third North Island Kōkako Recovery Plan emphasises management of the species on the New Zealand mainland. We are working on a revised recovery plan, aiming for it to be completed some time in 2017.
Ongoing effective predator control, genetic management, and improving the habitat quality of existing populations and restoration of kōkako to parts of their former range are key features of this plan.
Research by management
Our research focuses on increasing knowledge of the species to improve management efficiency to ensure long-term kōkako survival.
The 'research by management' programme which compared kōkako survival and productivity in three central North Island forests, has demonstrated that intensive management of introduced mammals can result in rapid expansion of kōkako populations.
At Mapara reserve in the King Country the total population more than doubled in seven years between 1992–1999. More importantly, the female population increased at least nine times over the same period.. A 2013 survey estimated the population at Mapara to be 123 pairs.
Similar techniques have been applied to locally threatened populations in Northland, Auckland, Waikato, East Coast and Bay of Plenty, where the birds are now increasing significantly.
A large, self-sustaining population established on Te Hauturu-ō-Toi/Little Barrier Island from translocations which took place during the early 1980s. This was used, together with kōkako from other locations, to create a new island population on Kapiti Island.
A survey in 2013 estimated 422 pairs on Little Barrier Island, and in 2016 there were an estimated >28 pairs on Kapiti Island.
A third island population begun on Tiritiri Matangi Island in the Hauraki Gulf during 1998. Tiritiri Matangi Island is holding kōkako of Taranaki lineage until a site at Taranaki is ready to receive them. In May 2017, kōkako of Taranaki lineage were returned to their ancestral home in Taranaki.
You can help
Community involvement is important for kōkako survival. The public have been involved with volunteered in survey, pest control, and monitoring work.
Community groups are involved mostly now with pest management to protect kōkako populations. Around half of existing kōkako sites are largely managed by community groups.
Help protect our native birds
When visiting parks, beaches, rivers, and lakes
- Only take dogs to areas that allow them, and keep them under control.
- Check for pests when visiting pest-free islands.
- Leave nesting birds alone.
- Use available access ways to get to the beach.
- Avoid leaving old fishing lines on beaches or in the sea.
- Follow the water care code and local navigation bylaws.
- Don't drive on riverbeds, or keep to formed tracks if you have to.
Other ways to help
- Get your dog trained in avian awareness.
- Volunteer to control predators and restore bird habitats.
- Set predator traps on your property.
- Put a bell on your cat's collar and feed it well.