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Kiwi distribution in Northland was surveyed during 1992, largely by listening for calls. Kiwi were recorded at 242 sites in six Ecological Districts. High call rates were recorded in the central and northern parts of Northland in forest remnants of varying sizes, but remnants over 100 ha had significantly higher call counts. Kiwi have declined in abundance and range in southern Northland since the late 1970s. Threats and potential threats to Northland kiwi include habitat destruction and deterioration, but particularly predation by dogs and other introduced mammals.

Observations of birds were made while working on fishing trawlers intermittently for a total of almost a year in New Zealand subantarctic waters. Large numbers of several species of albatrosses and petrels are attracted to trawlers to scavenge and their numbers vary throughout the year. Species not attracted are seen less commonly. Scavenging behaviour around trawlers is discussed. There seems to have been an increase in scavenging by certain species in the last 30 years.

There are major sexual differences in the calls of Thin-billed Prion Pachyptila belcheti. This allowed birds to be sexed initially by calls, and then by their measurements. Males were on average larger than females for six out of eight morphometric characters, with the greatest difference being in the bill. We then investigated the possibility of sexing birds on the basis of external measurements: a discriminant function analysis based on the eight measurements allowed correct classification of 84.4% of the 281 birds. In 89% of breeding pairs, males had greater bill depth than their partner. A stepwise discriminant analysis revealed that bill depth, head length and body weight were the three most discriminant variables. The combinations of two measurements (bill depth and body weight, or bill depth and total head length) allowed correct classification of 84.3 and 83% of the birds respectively, whilst a classification solely based on bill depth gave a 83.2% correct classification. The degree of sexual dimorphism in this species is similar to that found in other tubenoses.

Kaka (Nestor meridionalis) less than one year old can be distinguished from older birds by a pale ring of skin around the eye (periophalmic ring). In birds less than five months old this has a yellow tinge, as does the cere, gape and the soles of the feet. A further distinguishing feature of Kaka between three and six months of age are protruding rachides (feather quills) on the tips of the tail feathers. On Kapiti and Little Barrier Islands, most Kaka nestlings fledge in February and receive food from their parents until June or July. Fledglings can often be detected during this period by their conspicuous and frequent food-begging behaviour. Juvenile characteristics in the Kaka persist for a much shorter period than in the Kea (N. notabilis), its sole extant congener. The loss of juvenile characteristics prior to sexual maturity suggests that juvenile Kaka becomes socially independent of adults earlier than Kea, presumably because of more readily obtainable food sources in their environment.

Archaeological and palaeontological excavations were conducted as part of the Pitcairn Islands Scientific Expedition (January 1991 to March 1992). In this preliminary analysis of the subfossil bird bones from Henderson Island (24022( S, 12S018( E) we identified 29 taxa, which were divided into five groups: (1) four endemic extinctions, (2) five local extinctions, (3) a minimum of 12 breeding residents, (4) three non-breeding migrants, and (5) five birds of uncertain status. Over half of the landbird species known from Henderson Island are listed here for the first time, including one new genus and at least three new species. New listings for Henderson Island include: Henderson Archaic Pigeon (Columbidae new genus), Henderson Ducula Pigeon (Ducula new species), Henderson Ground-Dove (Gallicolumba new species), Henderson Sandpiper (Prosobonia new species), Royal Albatross, Little/Audubon’s Shearwater, Bulwer’s Petrel, Black-winged Petrel, Sooty Tern, cuckoo (Eudynamys sp.), and a swallow (Hirundo sp.). Most of the bird bones collected were associated with prehistoric Polynesian occupation sites dating from ca. AD 1000 to 1600. Humans may have caused the extinction of at least four of the eight endemic landbirds, which equates with similar extinction rates on other Pacific islands.

The New Zealand Shore Plover Thinornis novaeseelandiae is colourful and sexually dimorphic, which is unusual among plovers. T. novaeseelandiae is confined to Rangatira (South East Island) in the Chatham Islands. The sedentary population is relict. The mainland New Zealand population declined over the past century, probably as a result of predation by introduced rodents and feral cats. The population of about 130 birds includes 43 or 44 breeding pairs. There is no migration or dispersal from Rangatira. The population has been stable at least since 1969, but could increase by 12% per annum. Shore plover are long-lived. Survival and productivity are age- dependent. Mortality was highest among juveniles and for all birds in winter. Compared to other shore birds, adult mortality is low, and productivity high. The high proportion (20-35%) of non-breeding adults suggests that population increase may be constrained by a shortage of suitable habitat. Although the population appears to be stable at present, a single small population of a species is always in danger of extinction. A recovery programme now under way is aimed at establishing new populations.

During 1993, participants in the Beach Patrol Scheme patrolled 2954 km of the New Zealand coastline. 4295 dead seabirds of 55 species, plus 117 individuals of 28 other bird species were found. The number of seabirds found in 1993 was only 43% of the annual average of 9997 birds between 1971 and 1992, and was the eighth consecutive year that below average numbers of dead seabirds have been found. Unusual finds were three Yellow- nosed Mollymawks (Diomedea chlororhrynchos), two Grey-backed Storm Petrels (Oceanites nereis) and a New Caledonian Petrel (Pterodroma leucoptera). A summary is given of the coastal and monthly distributions of three Sterna species found between 1943 and 1992. Just nine Black-fronted Terns (S. albostriata) were picked up, mainly along eastern and northern South Island coasts. Of 239 Caspian Terns (S. caspia), most were found on Auckland West, Auckland East, Bay of Plenty and North Coast South Island beaches. There was no significant change in the recovery rate of Caspian Terns through the year. 1738 White-fronted Terns (S. striata) were found, with a peak in mortality during autumn.

A colour-banded population of Riflemen at Kowhai Bush, Kaikoura, New Zealand was studied to determine the contribution of males to the care of young. Parental care and territorial behaviour were qualitatively the same throughout the breeding period. Males fed the females during courtship and in this way contributed the food required to produce the first clutch of eggs. Males made 66% of nest-building visits (early nests), spent 50% more time incubating than their mate by day (both clutches), leaving the females the thermo-insular advantage of incubating at night, always fed young significantly more often than their mate and contributed 55-77% of all food items fed to broods without helpers (the great majority of nests), and shared territorial defence equally with their mate. However, nest-building and territorial defence occupied less than 1% of parents’ time early in the breeding season. One widower was unable to fledge young alone. Early season sex ratios for the years studied were (M:F) 22:15, 50:35, 39:37 and 20:21 with extra males sometimes becoming helpers. The male’s high parental effort was not reflected in significantly lower survival to the next breeding season. Possible reasons for the large contribution by the male Rifleman to the breeding effort are discussed.