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Sections of nine rivers in the Upper Waitaki Basin were surveyed between 1991 and 1994 and these surveys were compared with counts completed in 1962, 1965 and 1968. A systematic account of 27 wetland birds is given. Densities (number of birds km-1) of birds were compared between the two periods. Species that increased in density were mainly common generalists, whereas species that decreased in density were endemic river breeding specialists. Densities of Wrybills (Anarhynchus frontalis), Spur-wing Plovers (Vanellus miles), Canada Geese (Branta canadensis), and Grey Teal (Anas gracilis) were higher in the 1990s than in the 1960s, whereas densities of Banded Dotterels (Charadrius bicinctus), waterfowl and shags, Black-billed Gulls (Larus bulleri), South Island Pied Oystercatchers (Haematopus ostralegus), Black-backed Gulls (L. dominicanus) and Black-fronted Terns (Sterna albostriata) were lower in at least one river in the 1990s compared to the 1960s. Estimated minimum populations of river birds published for the Ahuriri River (surveyed in 1982) and the Cass River (surveyed in 1979 and 1982) were usually intermediate to those recorded in equivalent 1960s and 1990s surveys. Four mechanisms that explain changes in braided river bird populations are suggested.

Between March 1992 and February 1993, 222 five-minute stationary bird counts were conducted at 12 sites in the Kennedy’s Bush Scenic Reserve on Christchurch’s Port Hills. Over the period of the survey, 22 species of bird were recorded in or flying over the reserve. The seven most frequently recorded species were Silvereye (Zosterops lateralis), Grey Warbler (Gerygone igata), Bellbird (Anthornis m. melanura), Fantail (Rhipidura fuliginosa), Chaffinch (Fringilla coelebs), Blackbird (Turdus merula) and Redpoll (Acanthis flammea). Kennedy’s Bush does not contain a high diversity of native bush birds compared to some other mainland sites. Native species also appear less abundant in Kennedy’s Bush than in continuous, climax forest sites near Reefton. Kennedy’s Bush does, however, support high numbers of some species such as Silvereye, Grey Warbler, Fantail, Bellbird and Shining Cuckoo (Chrysococcyx l. lucidus) compared to sites at Kowhai Bush, Kaikoura. The autumn peak in numbers of Silvereye recorded at Kennedy’s Bush may result from flocks of migrating birds, some of which may move out of the reserve for the winter months. The numbers of Grey Warbler, Bellbird and Blackbird recorded probably reflect seasonal changes in conspicuousness rather than a change in actual numbers; adults are probably resident in the reserve year round. As in other parts of Canterbury, Fantail numbers were severely reduced by the heavy snow-falls of August 1992. Bellbird numbers were also reduced by the heavy snow-falls. Spring brought high numbers of Chaffinches to the reserve and summer brought high numbers of Redpolls, both of which were apparently absent or in very low numbers during winter. Small numbers of Goldfinches (Carduelis carduelis) and Greenfinches (Carduelis chloris) also appear to occur in Kennedy’s Bush only during the summer months. Of particular interest were records of two rarer Port Hills birds, Tomtits (Petroica m. macrocephala) and New Zealand Pigeons (Hemiphaga n. novaeseelandiae). Tomtits were recorded on only two occasions over the survey period. By 1997, however, this species appeared to be resident in the reserve. New Zealand Pigeons were recorded in Kennedy’s Bush in small numbers throughout the year and may breed there.

Dispersal of colour-banded South Island Pied Oystercatchers Haematopus ostralegus finschi from a breeding area on farmland in mid-Canterbury, New Zealand, was investigated from December 1987 to September 1997. Most moved north and were away from the breeding area from late December to mid-July. All birds spent this time at coastal sites, which ranged from 97 to 834 km from their breeding area. Distances travelled by males and females and birds of all ages were similar. Birds had high fidelity to wintering sites within and between years. Pair bonds were not maintained in winter and there was no evidence that fledglings accompanied their parents to wintering sites.

The sediment ponds and tidal flats at Port of Whangarei have been significant roost areas for waders since they were created from dredge tailing in the late 1960s. In 1971, 11 species of waders fed or roosted in this area; New Zealand Dotterel (Charadrius obscurus), White-fronted Tern (Sterna striata), Caspian Tern (S. caspia) and Black-backed Gull (Larus dominicanus) bred there, and on six islands of mud and shell. Intensive observation in 1979-80 and 1995-98 found that the residency status of many species had changed. There were significant declines in the numbers of New Zealand Dotterel, Caspian Tern and Skylark (Alauda arvensis), and significant increases in the numbers of Red- billed Gull (L. novaehollandiae scopulinus) and House Sparrow (Passer domesticus). These changes were associated with development of sedimentation ponds and increases in weed-stabilised communities and cover by mangroves. Future bird use of this area is very dependent on the management of the ponds, and the rate of encroachment of mangroves or ponds over the main mudflat roost area. A new island would safeguard wader roosting in the upper harbour.

Aspects of the ecology of the Antipodes Island Parakeet (Cyanoramphus unicolor) and Reischek’s Parakeet (C. novaezelandiae hochstetteri) were examined at the Antipodes Islands during October and November 1995. Significant differences in diet were detected between the species. Leaves of large tussocks formed the majority of the diet for Antipodes Island Parakeets, whereas tussock flowers comprised much of the diet of Reischek’s Parakeet. Significant differences in the diet of these species between this and previous studies were thought to reflect temporal variations in food availability rather than any fundamental shift in dietary preferences. Observations were made of both parakeet species scavenging on bird corpses. Antipodes Island Parakeets were also recorded killing and eating Grey-backed Storm Petrels (Oceanites nereis). One Antipodes Island Parakeet nest was located; clutch size, physical characteristics of the nest and of behaviour during incubation are described.

A colour-banded sample of New Zealand Snipe (Coenocorypha aucklandica) was studied on the Snares Islands over six breeding seasons. Snipe reached densities of 11.5 birds/ha; they were serially monogamous, but alpha males regained their original partner and territory at the start of the following breeding season. Up to 47% of males and 30% of females were excluded from breeding each year, although they were tolerated within breeding territories. Breeding adults were highly faithful to their territories and mates regardless of previous breeding success. About 83% of adults were seen in the study area the year after banding. No males moved to different territories, and only 11% of females moved, all to adjacent territories. Less than 9% of breeders changed partners between years if their previous mate was still present.Territory area was not influenced by intruder density: in years of high population density a higher proportion of birds was excluded from breeding. Non-breeding adults obtained a territory or mate only if a territorial bird died. Prior residence was an important factor in acquiring a territory both within and between breeding seasons. Mortality was density-dependent, and a relatively constant proportion of non-breeding birds was assimilated into the breeding population each spring.New Zealand Snipe were faithful to their natal area; 46% of fledglings were later seen in the study area. There was no sex bias in return rates, but females tended to disperse slightly further than males. About 11% of males and 57% of females bred as 1-year-olds. Previously non-territorial birds (beta status) gained access to territories and mates when alpha status birds were caring for chicks. No inbreeding was recorded.

We examined digestive tract contents and stable nitrogen isotope ratios (15N) in breast muscles of Buller’s Shearwaters (Puffinus bulleri) salvaged from squid and large- mesh driftnets in the central North Pacific Ocean. The epipelagic Pacific Saury (Cololabis saira) was the predominant prey, making up 71% of prey mass in digestive tracts. The remainder of the diet included small numbers of crustaceans, small fishes, and squids. The high degree of specialization in the diet seems to indicate that in the North Pacific, Buller’s Shearwaters usually feed at or near the water surface and rarely pursue food under water. Although these birds have been observed feeding on scraps from fishing vessels, our data suggest that offal comprises less than 10 percent of the diet. Stable nitrogen isotope values provided quantified information on the timing of arrival of migrants into the North Pacific.

A breeding male Chatham Island Taiko (Pterodroma magentae) was found recently dead of injuries by its burrow on 14 November 1996. Intraspecific fighting followed by sepsis of wounds seems the likely cause of death. All parts were preserved. Food items of Taiko include four squid species and one fish species. Its intestinal structure suggests a close relationship with the P. mollis group and P. macroptera. Measurements of bones indicate that most subfossil bones previously referred to this species were correctly identified.

Twenty species of birds are recorded from Kapingamarangi Atoll, southern Micronesia, 14 sea- and shorebirds and six land birds. Eleven are documented or probable breeders or former breeders. The Micronesian Starling (Aplonis opaca) is the only native, resident land bird, and it is common and widespread, averaging 5.7 birds ha-1 atoll-wide among the 31 islands. A kingfisher is reported from Kapingamarangi for the first time, and a recently collected specimen of Shining Cuckoo (Chysococcyx lucidus) is the first record for Micronesia and first report of the nominate (New Zealand) subspecies north of the Bismark Archipelago.

The diet of New Zealand King Shags (Leucocarbo carunculatus) in Pelorus Sound, South Island, New Zealand, was deduced from diagnostic prey remains in 22 complete regurgitated pellets collected as two samples taken six months apart. Pellets represented a total of ahour 683 prey items with an estimated wet mass of 14.9 kg. Witch (Arnoglossus scapha), a lefteyed flatfish (Bothidae), dominated the diet and accounted for about 90% of prey items and 95% of wet mass in both samples, but there was a change in the average size taken. The average total wet weight per pellet matched the theoretical estimate for daily energy expenditure for the shags. Prey species of interest to commercial or recreational fishers accounted for only 1.3% of the diet. These results are applicable only to the 25% of the species total population that forages in Pelorus Sound. An investigation of the diet elsewhere in Marlborough Sounds is recommended in order to determine if the small population size and restricted distribution of King Shags are related to the availability of food.