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Stephens Island provides the classic example in the New Zealand region of the effect that predation by feral cats (Felis catus) can have on an island land bird fauna. Twenty-five species of native New Zealand land birds were recorded on the island in the early 1890s when it was still forested and free of mammalian predators. It is probable that Stephens Island still had its original land bird fauna at that time. The land bird species included large populations of the extinct Stephens Island piopio (Turnagra capensis minor), and the endangered South Island saddleback (Philesturnus c. carunculatus). Cats were introduced to Stephens Island, probably in 1894. They soon became feral and multiplied rapidly. The evidence indicates that cats were responsible for the rapid demise of the native land bird fauna of the island.

Birds recorded on the Kermadec Islands, south-west Pacific, between 1967 and 1998 are summarised. Population estimates and distributions are given for the 24 breeding species. Brown noddy (Anous stolidus) is recorded breeding there for the first time. Information on breeding chronology for most breeding species is presented. Sightings of 53 non-breeding and vagrant species are summarised; 24 of these were new records since the last comprehensive review was published in 1970. The total bird list for the Kermadec Islands is now 80 species, including records of giant petrels (Macronectes), frigatebirds (Fregata) and oystercatchers (Haematopus) not identified to species. A further 16 species are included in a suspense list. The Kermadec Islands have only seven indigenous land birds, but retain a diverse seabird fauna, very similar to those of Norfolk and Lord Howe Islands. The land birds and seabirds of the largest island (Raoul) have been decimated by introduced cats (Felis catus) and rats (Rattus exulans, R. norvegicus). Introduced goats (Capra hircus) (since eradicated) drastically modified the vegetation of Raoul and Macauley Islands, and this also affected some bird species. Recommendations for restoration of the avifauna of these two islands are given.

Mainland colonies of Australasian gannet (Morus serrator) colonies at Muriwai, northwestem Auckland, New Zealand, were counted between 1999 and 2002. Fences installed in 1981 on the landward side of the colonies were removed at the end of the breeding seasons of 1996 (southern colony) and 1997 (northern colony). Counts 3 years before and after fence removal were compared. After fence removal, the total average number of birds during the peak breeding season (December and January) increased by 65%. The increase resulted largely from an increase in the average number of pairs nesting on the northern colony, and a small increase in the average maximum number of chicks on the northern and southern colonies.

Cook’s petrel (Pterodroma cookii), a New Zealand endemic, now breeds on only three islands at the extremities of its former range. Holocene fossil bones have indicated sites of 11 extinct colonies on North and South Islands, showing that Cook’s petrels preferred hills Gallirallus australis) have endangered these last colonies. Breeding success, most affected by rat predation of eggs and chicks, deteriorated seriously after extermination of feral cats from Hauturu, but improved significantly after eradication of rats from Whenua Hou. Rats are now a major threat on Hauturu. Cook’s petrels should be considered for reintroduction to suitable mainland reserves, to enhance biodiversity and restore nutrient inflows.

The taxonomic status of the endangered orange-fronted parakeet (Cyanoramphus malherbi)) has been the subject of much debate since this endemic New Zealand parakeet was first described in 1857. The debate in the late 1800s and again over the past 30 years has been lively but inconclusive. We provide a summary of this debate and the most recent research into the taxonomic status of this parakeet based on mitochondria1 DNA (mtDNA), assortative pairing, bill morphology, vocalisation, and comparative ecology. Based on all available scientific and historical data, we conclude that the orange-fronted parakeet is a distinct species.

Little is known of the causes of mortality in captive-bred brown teal (Anas chlorotis) released to the wild. To test whether feeding difficulties have contributed to the poor survival of released birds, we developed a method to detect starvation using the wing fat content of brown teal. We extracted the lipids from 4 outer wing components of 17 intact brown teal carcasses. The lipid content of each component reflected the birds’ nutritional condition (based on body mass and size, and visible fat). Lipids were also extracted from the outer wing components of 7 partial brown teal carcasses, 6 of which were from captive-bred released birds whose cause of death could not be determined. All of the released teal were found to have been in very poor nutritional condition immediately before death, implicating starvation as a factor in their deaths. Improving the feeding regime of captive-bred brown teal (pre- and post-release) is likely to increase their survival.

Bellbird breeding activity was monitored on Tiritiri Matangi Is in 1977 and 1978. The density of bellbirds breeding within the study area was 2.13 pairs ha-1. Resighting of banded adult birds in consecutive years was 69% and less than half the pair bonds were maintained into the following season. Breeding extended from Oct to Jan, with a peak in Nov. Most nests were built in tree ferns, and the mean clutch size was 3.6 eggs. Incubation and nestling periods were c. 12 and 14 days, respectively. The female bellbird was significantly more active than the male in care of the nestlings. Measurements of chick head and wing length were correlated with age. Nest success was 44%, and daily survival rate 97%. Predation, desertion, and exposure contributed to nest failure, and re-nesting was common. The mean number of nests female-1 season-1 was 1.3, while mean reproductive success was 2 chicks fledged. Young were independent 2 weeks after fledging, and moulted to adult plumage in their 1st year. The dynamics of the Tiritiri Matangi population, when compared with other populations, suggest that breeding behaviour is a flexible response to environmental factors, and will vary between populations depending on the level of predation, competition and habitat quality.

A quantitative survey of the bird community of Kaitoke wetland, Great Barrier Is., New Zealand between May 1998 and July 2000 using 5-minute counts recorded 33 species, most of which occurred in less than 10% of counts. The commonest species were North Island fernbud (Bowdleria punctata), fantail (Rhipidura fuliginosa), silvereye (Zosterops lateralis), grey warbler (Geygone igata), welcome swallow (Hirundo neoxena) and (collectively) the exotic finches, yellowhammer (Emberiza citrinella), chaffinch (Fringilla coelebs) and goldfinch (Carduelis carduelis). Native wetland species also recorded were spotless crake (Porzana tabuensis), banded rail (Rallus phillipensis), Australasian bittern (Botaurus poiciloptilus), pukeko (Porphyrio melanotus) and Australasian harrier (Circus approximans). Distributional analysis of the commonest species (those occurring in more than 10% of counts) showed most had some association with a particular vegetation type(s), while few showed any change in conspicuousness with season. There was little apparent movement of buds associated with phenology of the main wetland plant species. The sigruficance of Kaitoke wetland in providing habitat for a range of native wetland bud species is recognised. The current threat to this ecosystem from introduced pests and development pressure, and the paucity of data available on native wetland bird species to inform conservation management, is discussed.

The breeding success of northern New Zealand dotterels (Charadrius obscurus aquilonius) on Matakana Island, Bay of Plenty, was determined over 8 seasons (1992/93-1999/2000) in managed and unmanaged areas. Management to enhance breeding success included shifting nests to reduce the risk of flooding during spring tides and storms, and reducing predator populations of brushtail possum (Trichosurus vulpecula), feral house cat (Felis catus), Norway rat (Rattus norvegicus), stoat (Mustela ermines), and southern black-backed gull (Larus dominicanus) at dotterel breeding areas. Measures taken to reduce the incidence of disturbance by people on breeding dotterels included erecting fences around nesting areas, and speaking to members of the public about the plight of the species. The number of breeding pairs on Matakana Island fluctuated between 19 and 31 during the 8 seasons. Overall, 35.1% of 276 nesting attempts resulted in broods hatching. The main causes of nest failure during incubation were flooding by high tides or storms, and predation. The proportion of nests in which 1 or more eggs hatched was fairly stable during the 1993/94 to 1997/98 seasons at 26.1-33.3%, but was 68.0 and 51.3% in the last 2 years. This marked improvement in nesting success was attributed to the increased duration of pest control: starting before dotterel breeding began and continuing until most broods had fledged. Nesting success during incubation in managed habitat (47.5%) was significantly greater than in managed habitat (19.5%). Overall, 52.6% of chicks fledged. The number of chicks fledged per season (5 – 33), and fledglings produced per breeding pair (0.26 – 1.08) increased through the study In conclusion, we make suggestions to further promote the conservation of the northern New Zealand dotterel.