The hakawai was a ‘mystery bird’ formerly found on islands off Stewart Island; although never seen, its startling call was heard at night. The call of the hakawai, and its distribution and decline are described. The hakawai (under several spelling variations) is widely mentioned in myths and legends of the Maori throughout New Zealand; these records are summarised and the various theories for the hakawai’s identity are discussed. Evidence for non-vocal aerial displaying by New Zealand snipe (Coenocorypha) is presented. The hypothesis that the hakawai was an aerial display of Stewart Island Snipe (C. aucklandica iredalei) was investigated by comparing the distribution and decline of snipe with that of the hakawai, and by playing a tape recording of an aerial display of Chatham Island Snipe (C. pusilla) to people who had heard the hakawai. These data support the hakawai = snipe hypothesis. The historical distribution of Stewart Island Snipe included Big South Cape, Pukeweka, Solomon, Pourama, Jacky Lee, Herekopare, Ruapuke and Green Islands in the last 100 years. The extinction of snipe on these islands is attributed to introductions of ship rats (Rattus rattus, two islands), weka (Gallirallus australis, four islands) and a combination of weka and cats (Felis catus, two islands). It is proposed that subfossil remains of Coenocorypha from the North Island and the South Island be referred to C. a. barrierensis Oliver 1955 and C. a. iredalei Rothschild 1921 respectively.
A combination of searching for nests and responses to taped calls of Spotless crakes (Porzana tabuensis) was used to determine habitat use by and abundance of Spotless crakes and Marsh crakes (P. pusilla). Spotless crakes preferred to nest in scattered to dense tussock sedge (Carex secta) with an overstorey of raupo (Typha orientalis). Responses to taped calls indicated that they may have also nested in dense flax (Phormium tenax) and dense raupo. Limited information on Marsh crakes indicated that they nested in tussock sedge with little or no raupo overstorey.
During the 1977-1985 period a colony of 80-120 Little Shags (Phalacrocorax melanoleucos brevirostris) was studied at Hobson Bay, Auckland City. The breeding season of Little Shags was from August to March or April. Pied Shags (Phalacrocorax varius), which joined the colony during the study period and have tended to displace the smaller species, have nested throughout the year. For both species highest numbers of nesting pairs were present in spring (October – November). Little Shags of the pied form constituted one-third of the colony and interbred freely with birds of the white-throated and smudgy plumages. Fledglings have either the pied or totally black plumage and both can occur within the same brood. Aspects of behaviour are described and a detailed account of the colony is given.
During 13 days on Tongatapu and 9 days on ‘Eua (Kingdom of Tonga) I noted 16 and 20 species of birds respectively. I collected 5 species of reptile on Tongatapu and 3 on ‘Eua. Two species of ectoparasite from a Polynesian rat (Rattus exulans) were identified.
The number of Black-backed Gulls (Larus dominicanus) between the Otaki and Ohau Rivers, on the southwest coast of the North Island, has more than doubled in the last 25 years. There was a significantly larger proportion of subadults in 1961 than now, indicating that the population may have been in a growth phase in the early 1960s. The number of Red-billed Gulls (L. novaehollandiae) was about one-third of the 1961 level; this coincides with a sharp fall in the number of Red-billed Gulls nesting on nearby Kapiti Island. Numbers of other coastal birds were recorded and are discussed.
A genetic model is presented to explain plumage polymorphism in the Little Shag (Phalacrocorax melanoleucos brevirostris). Parent-offspring data from an Auckland colony show that expression of the three morphs (white-throated, smudgy and pied) is primarily controlled by two alleles at a single genetic locus. The allele specifying ‘dark’ (D) shows incomplete dominance over that specifying ‘pied’ (6). Comparison of morph frequencies with calculated genotype frequencies reveals that about 40% of white-throated birds are homozygous dominant (DD), the rest of the white-throated birds and all smudgy birds are heterozygous (Dd), and pied birds are homozygous recessive (dd). The population mates non-assortively and the Hardy-Weinberg law correctly predicts the frequencies of black and pied offspring from crosses. Morph frequencies (and allele ratios) show a gradient from north to south in New Zealand, dark birds being more common in the south. The main factor maintaining this cline may be climatic.