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The history of the kokako in the Hunua Ranges and contiguous districts is given so far as it is known. No literature prior to 1943 has been found for this area. J.W. St Paul’s sixty-five years experience of this bird, and, latterly, his work and that of others have proved that there has been a very serious decline in the population. Although seven nests were found between 1943 and 1953 only one, in 1962, was found in the nineteen years from 1953 to 1972, this in spite of intensive search in the later years. Fears for the future are entertained because exhaustive nest hunting efforts have failed for so long. Feeding is discussed, also the variation in songs and calls from those of further south. Of predators present Rattus rattus and the myna (Acridotheres tristis) are considered to be by far the most destructive agents and could well cause the extinction of the species here and elsewhere. Even if this bird does die out in the Hunua Ranges all this effort will at least have compiled much information and a certain amount of history.

In Auckland breeding occurs between late October and mid-April. During the 1970-71 breeding season 37% of territories were formed from undefended home ranges held during winter; remaining territories were created by non-residential pairs. Territories were defended by both sexes and averaged 0.83 ha. Mynas nest in holes and crevices. Nests average seven days to build. Average clutch size for aviaries was 3.9 eggs. Incubation begins with laying of the second egg and lasts 16 days for first egg of a clutch and 13 days for last egg. Nestling period is about four weeks. Only females sit on the nest at night. In total, 55% of all nests failed completely, and only 60% of pairs produced fledglings, from 24 single and eight double broods. Nesting success was 22%. Starvation of nestlings, disturbances and possibly shortages of food for adults were responsible for most mortality in nests. Similarity of open woodland and urban habitats, omnivorous feeding habits and hole-nesting have pre-adapted mynas for association with man. Mynas in Auckland, like several species of birds in European cities, did not experience shortages of food during winter and had smaller clutches, longer breeding seasons and higher densities than conspecifics in rural habitats.

New Zealand oystercatchers use specialised prey-specific methods to feed on common prey found in the marine littoral zone. Methods of locating and dealing with bivalves, limpets, chitons, gastropods, and crabs are herein described. Feeding behaviour may be modified by climatic factors, physical factors of the environment, and competition for food. The mainland species of oystercatchers have similar repertoires of feeding methods, but the South Island pied oystercatcher is behaviourally adapted to exploit estuarine bivalves whereas the variable oystercatcher is adaptively superior in exploiting limpets and chitons on rocky shores. The Chatham Islands oystercatcher seems behaviourally intermediate to its mainland congeners in feeding habits, possibly in response to widely varying feeding habitats in the islands. Differential niche utilization may therefore have been an important factor in the speciation of New Zealand oystercatchers.