There are species in New Zealand of so ancient a lineage that it is certain that they have been in this country since before the time when New Zealand first became an oceanic island or archipelago.
One of these species is the Kokako, belonging, with the extinct Huia and Tieke, the saddleback, to the ancient wattlebird family, Callaeidae. The common ancestor of these birds probably became isolated when the super continent, Gondwanaland, began to fragment some 80 million years ago. These birds are found nowhere else in the world, nor do they have any obvious living relatives.
Historically, the range of the Kokako has shrunk as its forest home has shrunk. Three quarters of the native forests present 1000 years ago before the arrival of humans have now gone. The mammalian predators that overrun the remaining forests and threaten Kokako today are quite different to the bird predators that hunted their ancestors a thousand years ago.
The dawn chorus of the Kokako was a common sound in the forest before European settlement. Indeed it was said to be far more numerous than the Tui but today one has to travel to one of the few areas remaining to the Kokako, such as the Mainland Island Restoration Project at Otamatuna in Te Urewera National Park, to hear its haunting song.
As the sunlight moves up across the bush to touch the tallest trees, the Kokako appears high in one of the trees on a ridge. It begins its morning performance by opening and closing its wings and fanning its tail. It then arches its neck and utters some gentle mewing and buzzing sounds before calling out across the valley. The incredibly beautiful melodious organ–like notes hang over the valley before being answered by another of its kind, somehow enhanced and made more poignant by the dark brooding quality of the bush. Male and female may sing together for periods of up to half an hour, performing a duet of impressive harmony and complexity. Neighbouring Kokako may join in singing the same themes, resulting in a rondo-like chorus.
The bird itself is as lovely as its voice. Predominantly blue–grey, the bill and legs are black along with a distinctive velvet black mask. The North Island species has ultramarine wattles under the throat. The South Island bird has orange wattles but this bird is now believed to be extinct.
It is only possible to distinguish the sexes after careful study of their behaviour as both sexes are very similar in size, colour and form. Like other wattlebirds, the Kokako flies poorly on short rounded wings. It prefers to use its powerful legs for leaping, running and jumping through the trees.
They eat a wide range of food, fruits, leaves and insects. They defend 5–20 hectare territories in which they obtain all their resources. Singing is used to maintain their territories. They sing mostly at dawn and always from the top of tall trees on ridges in the higher parts of their territory. In addition to song, Kokako communicate with a variety of calls, clicks, buzzes, cat–like noises and screeches, all used in particular social contexts. Pairs remain together all year and apparently for life, never being separated by much more than the distance of a quiet call.
Kokako reproduce slowly, a characteristic exhibited by many of New Zealand’s endemic birds. The immediate cause of Kokako decline is recruitment failure, the loss of offspring, due to predation by ship rats and possums at Kokako nests. In addition, many females are killed by predators while nesting. However, these declines can be reversed by intensive and sustained pest control.
According to a recently published document, less than 400 pairs of Kokako currently exist. Populations are small and isolated and most are male. The largest population by far is in the tawa dominated northern forests of Te Urewera National Park. The only other mainland island populations with more than 20 females are at Mapara and Pureora in the King Country and Kaharoa and Rotoehu in the Bay of Plenty.
The main objective of the Kokako Recovery Plan is to restore the species to most of its former range through Mainland Island projects throughout the country. It is an ambitious project and one that depends heavily on the ongoing generosity of the tax paying public. The war against predators must be sustained otherwise the monies already spent would be wasted.
McPherson Natural History Unit
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»»» Song of Korimako
Other common names: —
Blue wattled crow, Glaucopis wilsoni.
38 cm., 230 g., dark bluish-grey bird with a black facial mask, black bill, blue wattles. Juvenile has smaller pink wattles.
Where to find: —
In low numbers in forests of Northland, Bay of Plenty, Ureweras, Little Barrier and Kapiti Islands and Tiri Tiri Matangi.
More Information: —
South Island Kokako (Orange wattled crow)
Listen, Rosaleen. Out in the islands,
Lived a chief called Kupe, who was proud,
Once in a chase of Muturangi’s wheke
He by fortune found the Long White Cloud.
In his long canoe enseamed with sinnet
Past Te Kawa Kawa on he came,
There his daughters paused and plaited garlands
Of the leaf that gave the Bay its name.
Into this wide harbour came they softly.
“Ah,” said Matui. “two islands small.”
“One I name for thee,” said Kupe, laughing,
“One for Makaro, thy sister tall.”
Ere they sailed again for their own island
They looked long on leaf and flower and loam,
Their dark eyes went searching, searching, searching,
Then they bore the tidings home.
There unto the tribe they told their story,
“But,” said Toto, frowning in the sun,
“In that land of blossoms, bays, and rivers,
Of its men-folk saw you not a one?”
“None saw I,” said Kupe after silence,
“No man saw I there by shore or hill,
But I saw a little Tiwai-waka,
And a Weka tilted up at me his bill.
“But,” said Toto, wrinkling in his wonder,
“Did the land lie silent, dead, and lone?”
“Only one bird heard I through the stillness,
A Kokako Ko-ing on a stone!”
In the Kauwae-Raro you will find it,
Find great Kupe’s true and simple word,
How he heard the call of the Kokako,
And no other crying bird.
Little heart, be proud of the Kokako,
For it is our own, and very old,
May it Ko for ever on the ridges,
May it Ko until the sun turns cold.
— Eileen Duggan
Illustration description: —
Buller, Walter Lawry, Birds of New Zealand, 1873.
Buller, Walter Lawry, Birds of New Zealand, 1888.
Hay, J.R., Best, H.A., Powesland, R.G., Kokako, NZ Wildlife Service, 1985.
Page date & version: —
Sunday, 10 October, 2010; ver2009v1