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Petrels, especially Procellariidae and Hydrobatidae, visit their breeding places in lesser numbers on moonlit nights than on darker nights. This is probably caused by poor feeding conditions because prey do not come so near the surface on moonlit nights. Fledgling petrels, mainly Procellariidae, are particularly liable to be attracted to artificial lights situated near the breeding colony. It is suggested that nocturnal-feeding petrels are instinctively attracted to light sources because they exploit bioluminescent prey. A small proportion of fledglings seem to be initially misled by this instinct.

The distribution, speciation and probable evolution of New Zealand parakeets are outlined. Specific ecological adaptations keep closely related sympatric species separate. Examples are given of such ecological isolating mechanisms in Antipodes and Chatham Island parakeets. Occasionally, where man has drastically modified the environment, these barriers break down and widespread hybridisation occurs, as on Mangere Island, Chatham Islands. The existence of the very rare Chatham Island yellow-crowned parakeet (Cyanoramphus auriceps forbesi) is endangered by habitat changes and hybridisation.

Observations and data are presented from an expedition to Korapuki Island between 25 November and 2 December, 1974. The vegetation composition and communities are mapped and a checklist of plant species identified and compiled from this and former expeditions is presented. Seven species of seabird are now recorded as breeding on Korapuki Island and their respective burrow distribution and density is outlined. A breeding record of the sooty shearwater is the first for the species breeding on this island. The grey-faced petrel is the most abundant breeding seabird on the island with an estimated 600–700 pairs. Fifteen species of bush bird are noted, of which the shining cuckoo, long-tailed cuckoo and morepork are new records. Four of the five lizard species previously collected from this island were found, the exception being Sphenomorphus pseudornatus. It is considered that the habitat of Korapuki Island is marginal for this species. Stomach examination of rats trapped on the island reveal a high frequency of occurrence (49%) of bird remains. The rabbit population is considered low compared with data collected from previous expeditions. The soil and litter fauna showed a lower diversity and abundance than that found on the adjacent Coromandel mainland. Large invertebrates were noticeably rare, due possibly to predation by rats. An incidental insect list is also presented.

Ten samples of South Island pied oystercatchers (Haematopus ostralegus finschi) were trapped between August 1969 and June 1971. Nine catches were made at the Heathcote-Avon estuary and one at Parapara Inlet in northwest Nelson. In late summer large numbers of immatures and adults arrived at the estuary. Decreasing frequencies of juveniles in later samples suggest that young birds tend to move further north than most adults. Males outnumbered females in all samples except the one in February 1971 when there was an excess of females. This seasonal shift in sex ratio could arise from a staggered migration and/or differential mortality of the sexes. Further systematic trapping at strategically placed coastal haunts is needed to substantiate and elaborate the above findings.

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.