North Island Kokako

Callaeas wilsoni - Glaucope de Wilson

Systematics

Order
:
Passeriformes
Family
:
Callaéidés
Genus
:
Callaeas
Species
:
wilsoni

Descriptor

Bonaparte, 1850

Biometrics

Size
: 38 cm
Wingspan
: -
Weight
:

Longevity

20 years

Geographic range

Distribution

Identification

The North Island Kokako, an endemic species, evokes the forests of old New Zealand more than any other species. You are more likely to hear it than see it. Small populations have survived particularly in the North Island's center and in Te Urewera National Park. It is a typical inhabitant of the high native forest dominated by the tawa tree (Beilschmiedia tawa). Continental populations on the North Island persist only through sustained control of introduced mammalian pests (Rattus norvegicus and Trichosurus vulpecula). All unmonitored populations have gone extinct.

Subspecific information monotypic species

Foreign names

Glaucope de Wilson,
Kokako de Isla Norte,
cocaco-de-barbela-azul,
Graulappenvogel,
Noordelijke Kokako,
nordökokako,
Nordkokako,
laločník lesný,
Nordkokako,
kookako,
kokako,
koralnik modropłatkowy,
Северный кокако,
ホクトウハシブトホオダレムクドリ,
北岛垂耳鸦,
nordökokako,
北島垂耳鴉,

Voice song and cries

play
pause

The North Island Kokako sings throughout the year generally at dawn and dusk. Its song is a slow and resonant melody that resembles an organ. Sometimes males and females sing in unison from an elevated perch.

Habitat

They reside in diverse native upland forests, usually in a mixed tawa or Taraire forest with podocarps or Kauri. They are successfully breeding in mixed broadleaf and densely scrubby forests planted on Tiritiri Matangi Island.

Behaviour character trait

North Island Kokako defends a large territory throughout the year with complex songs, including in duos with the female. Juvenile dispersal is typically 1.3 km before settling on a territory. Their populations are easily isolated by forest fragmentation. Mist netting is commonly used for their capture with Japanese nets.

Flight

It's a poor flyer. They usually perch on trees, move by hopping through the branches, perform short flights, but can also glide for several hundred metres from the top of the trees.

Dietfeeding habits

They primarily feed on fruits, leaves, less often flowers, moss, buds, nectar, and invertebrates.

Reproduction nesting

They generally nest between November and February, after which they molt. The breeding season can last 6 months and there can be up to three clutches in years with high food production.

The nest is located at an average height of 13 m. Two to three pinkish gray eggs, spotted with brown or brown-violet, are laid, and only the female takes care of incubation. The nest is an elevated platform, in the form of an expanded cup. Various vegetation is placed on this platform composed of twigs placed on clumps of epiphytic plants, bordered by tree ferns. Incubation is done by the female alone for 18 days. The two adults feed the chicks. They leave the nest between 32-37 days, and will be completely independent after several months. At the time of fledging they usually stay in the parents' territory for several months, up to a year, while still being fed by the adults. The maximum dispersal is usually less than 2 km from the nesting site.

Geographic range

North Island Kokako populations are limited to a few scattered forests in the North Island, particularly in the Waikato, Bay of Plenty and Te Urewera National Park. Since 1981, reintroductions have occurred on Little Barrier Island, Kapiti Island, Tiritiri Matangi, Bruce Mountain Scenic Reserve (Wairarapa), Island Mainland Boundary Stream (Hawke's Bay), Ngapukeriki (East Cape), Ark in the Park (Waitakeres, west of Auckland), Whirinaki and Otanewainuku.

Threats - protection

IUCN conservation status

Extinct

Threatened

Least
concern

Extinc
in the Wild

Near
threatened

Not
evaluated

EX EW CR EN VU NT LC NE

The North Island Kokako is classified as critically endangered by the IUCN. Predation of nests by rats and possums is the main cause of its disappearance. All current populations must be constantly monitored in order to fight predation by introduced mammals. Controlled and repeated regulation of pests on the continent and in the islands is necessary. Rats and possums are regularly targeted by trapping and poisoning with 1080 during breeding season. The amount of food available affects the number of breeding pairs. Several key populations are restored through the reintroduction of young females from different source populations. The maintenance of genetic health also has an influence on the management of the species.

Illustration

Access to all images

Sources of information

IOC World Bird List (v14.2), Gill, F and D Donsker (Eds). 2024-04-18.
xeno-canto, Sharing bird sounds from around the world,
ARKive, Christopher Parsons
Avibase, Lepage Denis
Conservation-comments-NZ,
New Zealand birds and birding, Narena Olliver
IUCN Red List of Threatened species,
Handbook of the birds of the world Vol.14, josep del Hoyo

Other sources of interest