Kokako Rescue Bay of Plenty

Forest and Bird, Volume 21, Issue 2, 1 May 1990, Page 6

Kokako Rescue Bay of Plenty

Sioux Bennett

E MIGHT WELL BE SOME KIND OF BUSH AMADEUS. Fingers poised, he considers the keys before applying his hands to them with dexterity, listening carefully to the results of his skill. From selected corners of the darkened undergrowth, the kokako's clear notes resound, magically reproduced by some unseen bird. Surely any unwary kokako would be fooled. Paul Jansen isn’t so sure. He hunches over his tape recorder, playing the call again in a different sequence in an effort to musically summons the kokako known to be in this segment of the Rotoehu forest. And his patience is rewarded. From high above, real song is returned. The single kokako whooshes through the tree tops, searching for its re-created companion. Paul frowns, adjusting the taped song to lure the kokako in the right direction. It’s almost too easy. The bird makes a high pass to our right and flies straight into the giant mist net strategically erected between two tall trees slightly doctored for the purpose. Caught between the 70ft net’s fine double mesh, the kokako struggles slightly, confused about what has happened and squeaking pathetically. The net is lowered and Paul and his colleague, John Innes, gently untangle the bird. Before much longer, the surprised kokako will be given a nourishing meal of Farex to restore its spirits before enduring the ordeal of having a transmitter attached to its neck and then being released. The kokako staggers off into the bush, shimmying up the nearest tree to escape before finally flying away. The Department of Conservation (DoC) and the Forest Research Institute (FRI) are six months into a pilot research programme in Kaharoa state forest and Rotoehu forest near Rotorua to evaluate the relative roles of browsers and predators in North Island kokako decline.

Since 1980, predators have destroyed eggs or young birds in 11 of the 24 nests of known outcome and the considerable overlap between the diets of kokako and of possums, goats and deer is another factor which has to be considered if kokako are to survive. However as John Innes of FRI notes, the project doesn’t assume either browsers or predators are responsible for the kokako’s decline — and will rather accumulate data stacking the odds one way or another.

He says the primary aims of the 15 month programme are: To compare breeding attempts and outcomes on Little Barrier Island with those at Rotoehu, compare kokako condition and time spent feeding at both locations, identify predators, estimate kokako longevity, mean life expectancy, territory size and juvenile survival and to compare available food quantity at Rotoehu and on Little Barrier. To do that a number of techniques have been employed to follow as many kokako pairs as possible through each breeding season and find out whether an attempt was actually made to breed. "That's where the radio transmitters come in. We capture at least one of each kokako

pair and put the transmitter on. That moults off after each breeding season and doesn't hurt the birds. It also means we have to recapture them again each year to re-attach the transmitters." The kokako caught are also weighed, measured and colour-banded. By early March 1990, four kokako pairs have been traced. The techniques have proved to work. John Innes is delighted. But only one of the pairs had tried to breed -and the attempt failed badly. A nest containing three ravaged eggs was discovered in the forest in February, apparently preyed on by another species of bird. It was the first real proof of kokako breeding failure, with the eggs preyed on within a short time. The study's succes0000000 means it will now be expanded into the next breeding season to include up to 15 bird pairs and will extend to include the comparisons with predator-free Little Barrier Island — while work continues at Kaharoa with a different sort of survival programme. Somewhat more "glam", the project is a joint effort between Tasman Forestry Ltd, the Royal Forest and Bird Protection Society and Doc, funded by a special $150,000 grant from Tasman as part of the landmark Tasman Accord which protects important areas of kokako habitat. It also differs from the Rotoehu programme by aiming to actually control predators such as rats, stoats and wild cats and browsing animals in one of five research and management projects currently underway in the North Island. (The others are at Mapara, near Te Kuiti, Puketi Forest in Northland, the Cowan Wildlife Refuge near the Pureora Forest Park and the Pikiariki Ecological Area within the park). The three year project is headed by Hazel Speed, an expert with extensive experience in New Zealand wildlife and kokako. &