There are two species of native pigeon: the New Zealand pigeon (Hemiphaga novaeseelandiae) known to the Maori as kererū, or in Northland as kūkū or kūkupa; and the Chatham Islands pigeon (Hemiphaga chathamensis) or parea.
While kererū are not threatened, parea are considered nationally vulnerable.
Two other kinds of native pigeon became extinct on Raoul Island and Norfolk Island last century, probably due to hunting and predation.
Large birds with large bills
Kererū are large birds and can measure up to 51 cm from tail to beak, and weigh about 650 g. Parea are around 20% heavier.
Since the extinction of the moa, the kererū and parea are now the only seed dispersers with a bill big enough to swallow large fruit, such as those of karaka, miro, tawa and taraire. The disappearance of these birds could be a disaster for the regeneration of our native forests.
The birds also eats leaves, buds and flowers, the relative amounts varying seasonally and regionally, eg in Northland they eat mostly fruit.
Long-lived birds, they breed slowly. Key breeding signals are spectacular display flights performed mainly by territorial males. They nest mainly in spring/early summer producing only one egg per nest, which the parents take turns to look after during the 28-day incubation period.
The chick grows rapidly, leaving the nest when about 40 days old. It is fed "pigeon milk", a protein-rich milky secretion from the walls of the parents' crops, mixed with fruit pulp. When much fruit is available, some pairs of kererū will have a large chick in one nest and be incubating an egg in another nearby. Fledglings spend about two weeks with their parents before becoming fully independent, but have remained with their parents during autumn and winter in some cases.
Although still quite widespread in areas with large tracts of forest, its numbers are in gradual decline through habitat loss, predation, competition and illegal hunting.
The decline has been offset due to recovery on predator-free offshore islands, or from large-scale recovery at sites with widespread pest control.
Although the kererū was traditionally hunted for its meat and feathers, hunting of the bird is now illegal.
The most serious threat to the kererū comes from predators. Recent studies in several parts of the country have found that many nests produce no chicks at all. Rats, stoats, cats and possums eat their eggs and young.
Possums also compete with adult kererū for food (leaves, flowers, fruit) and devastate trees by consuming new shoots. Stoats and cats will attack and kill adult kererū. Forest clearance and poaching are also threats to its survival. Research by the Department of Conservation, Landcare Research, universities and other groups has found that the species is unlikely to cope with hunting pressure.
In Northland, the kūkupa is in danger of becoming locally extinct through the combined effects of predation, competition and continued hunting.
The Department of Conservation carries out large-scale pest control operations. These assist the recovery of kererū by killing the predators that prey on their eggs and chicks. By controlling rats and possums, kererū populations can increase by 50 percent in two years.
We are also involved in educating the public about the plight of the New Zealand pigeon and encouraging local initiatives to save it.
In Northland, we have been working with local iwi to help stop illegal poaching of the kūkupa by educating young Māori about the disastrous effect this is having on the birds' survival rate.
You can help
There are lots of ways you can protect kererū in your region:
- Control predators (possums, cats, rats and stoats) in your bush by trapping or poisoning.
- If you find an occupied nest and trapping/poisoning is not an option, band the tree and interconnecting trees to exclude predators.
- Consider planting trees to feed the kererū. Tree lucerne is useful in the short-term as it flowers prolifically in winter and grows quickly; for a long-term solution, plant miro, titoki, tawa, fuchsia, kōwhai, five-finger, pate, pigeonwood, taraire, puriri and wineberry.
- Do not hunt kererū.
Find more ways to get involved by visiting these websites:
Help protect New Zealand's native birds
- Volunteer with DOC or other groups to control predators and restore bird habitats.
- Don’t throw rubbish into water ways or storm drains.
- Set traps for stoats or rats on your property. Get more information from your local DOC office.
- Put a bell on your cat's collar. Feed your cat well, and keep it indoors at night.
- Plant a range of native plants that provide food year-round to encourage birds into your garden.
When visiting parks and beaches
- Only take dogs to areas that allow them, and keep your dog under control.
- Prevent the spread of pests. Check your gear for mice and rats when visiting pest-free islands.
- Use available access ways to get to the beach. Stay out of fenced-off areas. Leave nesting shore birds alone.
- Get your dog trained in avian awareness, and help save forest birds like kiwi and weka.
- Follow the water care code. Keep water craft speed to 5 knots within 200 metres of the shore.