THE CAGOU

Forest and Bird, Volume 15, Issue 2, 1 May 1984, Page 31

THE CAGOU

by

Rod Hay

A QUESTION OF SURVIVAL

In remote mountain valleys of New Caledonia, small numbers of cagou (kagu), the flightless bird that is the symbol of that territory, Stalk the forest floor in search of invertebrate food. Their continued survival is not assured, but it is subject to the attention of a few dedicated workers. Even here in the tropics, the dawn air imparted a chill to bare arms and legs as we waited, seemingly vainly for sound of the bird we had come to find. As the colours of day began to paint the sky, adawn chorus of many small birds began to piece itself together. Dominated by Meliphagids, the grey cheeked honeyeater, the barred honeyeater, the New Caledonian friarbird and the occasional clicking calls of the giant crow honeyeater, the sound became almost deafening. Finally, once the sun had begun to graze the ridgetops, a loud rhythmical yodelling or baying came from across the valley. This sound was joined by others until nearly a dozen cagous were whooping and yelping ina cacophony most unbirdlike in nature. The family Rhynochetidae consists of the single species Rhynochetos jubatus, which is confined to the main island of New Caledonia, La Grande Terre. Though recent subfossil discoveries on Isle des Pins suggest a broader distribution previously, the cagou has no close relatives anywhere in the world, with the possible exception of the enigmatic but extinct Aptornis of New Zealand. It thus comprises an endemic family of very uncertain affinities but perhaps with some connection with the herons and the rails. It is little wonder that eminent ornithologist, Ernst Mayr, proclaimed it as one of the most peculiar birds of the South West Pacific region. While they are large (adults weigh approximately one kilogram and stand up to 500mm tall), cagous are very rarely seen in the wild, being identified usually by the brief bouts of raucous dawn calling or as the occasional prey of over-zealous pig dogs. The bird presents a strange appearance, ghost-grey plumage in stark contrast to the cryptic tones of flightless birds with which we are more familiar. Perhaps the most conspicuous feature is the long crest of pale grey feathers which is erected in display. The wings, while not used for flight, have an impressive barring of white, black and brown when also held out in display. For asad comment on human attitude to wildlife, we only need to make a cursory survey of national or territorial symbols around the world to see symbols of rarity and abuse. Just as the bald eagle in North America, the condor in South America and our own kiwi have suffered, the cagou’s survival is precarious and in the face of human induced hazards. Restricted now to

certain isolated parts and with numbers uncertain (they are very difficult to census), the species suffers a variety of threats. Dogs used for pig hunting are known to catch adult cagous, wild cats are equally dangerous and pigs, known to prey on adult petrels, probably also compete for Placostylus snails and other invertebrate food. The ship rat (Rattus rattus), is also common in New Caledonian forests and is a likely predator of eggs and chicks of the ground-nesting cagou. Despite this onslaught of predators, the species has survived until now, so perhaps the greatest threat is the continual erosion of available habitat. During the nickel boom between 1970 and 1980, open-cast mining laid waste to vast areas of the country and this has consorted with an increased human population pressure and accessibility to place the species under further stress. What is being done to give the cagou a fair chance? Firstly, the establishment of a network of territorial parks and botanical -eserves is some assurance that habitat remains. Much of this is dangerously accessible to hunters, but at least one area, le Parc Territorial de la Riviere Bleue, contains several thousand hectares of cagou habitat and is remote enough to allow greater protection. Even there, however, the building of a hydro village in the middle of the park has recently been narrowly averted. The second approach to conservation of the species is a captive breeding programme. The Service des Eaux et Forets and the Societe d’Ornithologie Neo-Caledonienne have established large aviaries in the Parc Forestier near Noumea where several pairs of cagou are kept. Remarkably, the birds become very tame and approachable when in captivity and successful nesting there has resulted in the raising of nearly

twenty juveniles since the programme began in the late 1970s. This result is in marked contrast to the complete failure of attempts to breed this species in zoos elsewhere in the world. The ultimate aim of the captive breeding programme is to supplement the wild population with mature birds, capable of fending for themselves. Responsible for much of this operation is Yves Letocart, ranger responsible for the Riviere Bleue park and co-author with Francis Hannecart of arecent two volume book on the birds of New Caledonia. Yves has constructed a large ‘‘pre-release hostel’ in the park, where captive-reared birds practise fending for themselves before liberation. While these birds may be an important supplement to a dwindling wild population, it is important to know something of their chances of survival. For a species which is difficult to observe as this one, radio tracking of individuals may provide the only reliable data. With this in mind, Messrs Letocart and Hannecart have recently been touring New Zealand, hosted by Royal Forest and Bird, Wildlife Service, Forest Service, DSIR and the Department of Lands and Survey to study radio tracking and wildlife survey techniques, and general aspects of nature conservation. If the cagou is to continue to survive, then we need more accurate information on the size and distribution of the population and the factors affecting it. This should involve the establishment of a trained survey team and support for the tracking study already planned. The International Council for Bird Preservation is raising funds for these projects and is grateful for the support of Royal Forest and Bird in helping to assess bird conservation needs in the southwest Pacific. se