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During a census in gardens in Hamilton, 71.8% of the 4428 birds observed belonged to introduced species. A total of 15 species were observed. Bird species richness was positively correlated with native plant biomass and, more strongly, with total plant biomass. More birds were present in gardens with more native plants. Among the most common species, the abundance of the House Sparrow (Passer domesticus) decreased with increasing percentage of native plants, the Silvereye (Zosterops lateralis) increased, while Blackbirds (Turdus merula) and Starlings (Sturnus vulgaris) showed no significant change. This was typical for a other introduced bird species. Most other birds, including the Fantail (Rhipidura fuliginosa) and the Grey Warbler (Gerygone igata), were most abundant in gardens with higher native plant biomass. Notable was the absence of the Tui (Prosthemadera novaeseelandiae) from all censused areas in Hamilton at the time of observation. No significant variation between morning and evening samples was noted.

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.

Between 1940 and December 1993, 66 species of landbirds (including shore and freshwater birds) were recorded at the Chatham Islands. Of these, 38 were native and introduced breeding species, 4 were regular summer visitors and 24 were occasional visitors or stragglers. Published and unpublished records of these species on the Chatham Islands are summarised.

The diet of Red-crowned Parakeets (Cyanoramphus novaezelandiae chathamensis) and hybrids (C. n. chathamensis x C. auriceps forbesi) was determined from crop contents and field observations. Crops were dissected from 220 Red-crowned and hybrid birds collected over four years on deforested Mangere Island in the Chatham group. Volume and prevalence of foods taken in winter, spring and summer were measured. No effect of sex or age was found on frequency of occurrence of food items, and low variation in diet attributable to species hybrid status indicated that feeding strategies of the parent species had converged. Diet of all forms varied seasonally. The main winter food was grass seeds, with a small proportion of leaves. The spring diet was the most varied, consisting mostly of leaves, with seeds, flowers and invertebrates. Seeds were eaten in late summer, mostly from Geranium traversii. Field observations in winter emphasised the importance of leaf feeding. Some plant species seen to be eaten in summer were not found in crops. Habitat selection and perch height distribution was associated with breeding requirements as well as feeding.

Brown skuas (Catharacta skua lonnbergi) on rangatira (south east) and mangere islands in the chatham islands group were studied over a period of 14 years (1978/79 to 1992/93 breeding seasons) to determine factors promoting cooperative breeding in this population. The size and composition of the breeding population and overall breeding success were remarkably stable. No significant differences in breeding success, density of territories or periods of individual occupation in different places on these islands were demonstrated that would demarcate optimal and marginal breeding habitat. Neither could it be demonstrated that the islands were saturated by breeding birds as required for a habitat-forced origin of cooperative breeding.