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The distribution of the North Island kokako (Callaeas cinerea wilsoni) in the western King Country and Taranaki was recorded during summer 1980-1981. The survey confirmed that the kokako was widespread in the study area but showed that its range is continuing to shrink. The status of many populations is still uncertain. Kokako appear to have disappeared recently from large forest tracts in south-eastern and inland Taranaki and from large isolated forests in the north. Within large forest tracts kokako were not recorded in some locations where they had been present before 1970. Most kokako were in unmodified rimu-tawa dominant forest and habitat deterioration appears to be an important factor in their decline.

Evidence is described indicating intraspecific nest parasitism in the white-throated munia (Lonchura malabarica). The munias seem to prefer breeding in abandoned nests of weaverbirds (Ploceus spp.) and have little tendency to make their nests in the open. The scarcity of deserted weaverbird nests suitable for occupation by munias seems to be the main reason for the development of this intraspecific nest parasitism. The possibility of the white-throated munia becoming a nest parasite of weaverbirds is also discussed.

Bird numbers and habitat preferences were noted regularly for 3 years on the delta of the Cass River, Lake Tekapo. Species counted were an oystercatcher, three plovers, two stilts, two gulls and two terns. Most species left the area after breeding and numbers were highest during spring. The river mouth and lake shore were most used in late winter and early spring before all species moved away to forage and nest in other habitats, particularly on the shingle riverbed and adjacent river terraces. Seasonal patterns were modified by rapid artificial changes in lake level, by excessive river flooding, and by snow-storms.

From 1963 to 1981 data were collected on the breeding of the Buller’s shearwater (Puffinus bulleri). The world population, roughly 2.5 million birds, occupies 7 of the 12 islands, islets, and stacks of the Poor Knights Islands (35°30’S; 174°44’E). Buller’s shearwaters return from their 4.5 month trans-equatorial migration on about 10 September. Numbers build up rapidly with breeding birds digging burrows averaging 1.01 ± 0.2 m in length. Caverns, caves, and Maori stone walls also serve as nest sites. Nest refurbishing is complete by about 26 October, when copulation occurs. The prelaying exodus follows about 32 h later, with most birds absent from the isIands’ vicinity for about 30 days until 25 November. Eggs appear from 26 to 30 November. Females without nests lay eggs on the ground until 3 December; these eggs are eaten by tuataras and small lizards. Average dimensions of 74 eggs were 65.44 ± 0.29 x 42.96 ± 0.22 mm; and average weight of 27 fresh eggs 66.76 ± 0.85 g. Surface eggs are narrower than burrow eggs. The incubation period is c. 51 days with both sexes sharing duties. Four nights is the average shift; females sit the first night and following day. Hatching occurs about 19 January; most fledglings leave the islands in early May. Most of the few adult P. bulleri that die on the breeding grounds are ensnared in tree saplings. Numbers on Aorangi have expanded rapidly from c. 100 pairs in 1938 to about 200,000 pairs in 1981. P. bulleri is an aggressive coloniser, displacing gadfly petrels and smaller shearwaters for nesting space. and may soon be colonising the Three Kings and other nearby islands.

An albinistic juvenile Australasian harrier (Circus approximans gouldi) was trapped near Huntly, Waikato. Limited observation of the bird prior to capture suggests that its general behaviour and relationships with conspecifics and other species were normal. The bird’s plumage is described and contrasted with that of normal harriers and the nature of its soft parts is discussed. Other occurrences of aIbinism in the Australasian harrier are given.

In central Westland, 110 western wekas (Gallirallus australis australis) were marked between August 1975 and May 1978, and 38 corpses were examined. Wekas occurred throughout the study site but preferred ecotonal scrublands while avoiding dense forest. Captures fell by 50% over the study period and the number of sightings also decreased significantly. Adults were sexed by a discriminant function based on the bill measurements of dead birds, with a probability of misclassification of live adults of about 4.6%. A sex ratio biased towards males was revealed. Breeding began in late June/July when both sexes had attained maximum annual body weights and fat reserves. Home ranges were generally less than 4.5 ha. The main foods identified from birds collected during June-August and in November were fruits of indigenous forest plants, especially Coprosma spp., and plant foliage, insects and earthworms.