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The total population of North Island weka (Gallirallus australis greyi) is about 4150 adults spread over five islands, one North Island population, and a number of captive birds in aviaries and mainland island programmes. Between 77% and 84% of the adult weka population are on Kawau Island. Density changes in the Mansion House Historic Reserve, and anecdotal records suggest that adult weka populations on Kawau Island has fluctuated between c.2100 and c.5000 during 1992-1999. The largest declines occurred within 12 months of the 1990-91 and 1997-98 droughts.

Snares Island Snipe (Coenocorypha aucklandica huegeli) were studied on the Snares Islands during parts of six breeding seasons between 1982 and 1987. Laying was between 4 November and 19 February; the breeding season (including chick-rearing) spanned the months November to May. Nests were well concealed among dense vegetation with solid overhead cover. Most birds were monogamous, with shared incubation of the two-egg clutch. Males incubated for 51% of the time, mainly at night and during late afternoon; females incubated 49% of the time, mainly during the morning and early afternoon. The eggs hatched synchronously and the chicks stayed in the nest for less than 13 h. The male cared for the first chick to leave the nest. Growth of chicks is described using Gompertz equations. Full juvenile plumage took c. 54 days to attain, and adult size in all growth parameters was attained soon after independence (c. 65 days).Chatham Island Snipe (C. pusilla) were studied on Rangatira Island during the 1983-84 breeding season. Laying was estimated to extend from late September to the end of December. Most nests found (86%) were under Carex sedges. Incubation of the two-egg clutch was shared; incubation patterns were not determined. The eggs were 19% smaller in relation to predicted egg-weight than those of Snares Island Snipe. The eggs hatched synchronously and the chicks stayed in the nest for less than 11.5 h. The male cared for the first chick to leave the nest. Full juvenile plumage took c. 47 days to attain. The bill grew much more rapidly than for Snares Island Snipe and chicks became independent much earlier (c. 41 days old).

The growth of New Zealand’s second mainland Australasian gannet (Morus serrator) colony at Muriwai, north west Auckland is described from counts between 1975 and 1998. The colonies on Motutara Island, and the southern and northern colonies on Otakamiro Point have increased from 28 pairs in 1975 to 1393 pairs in 1998. The potential for future colony expansion on the northern cliff face, where human disturbance is highest, is discussed.

We observed that South Polar Skuas (Catharacta maccormicki) breeding near the Adelie Penguin (Pygoscelis adeliae) western colony at Cape Crozier, Ross Island, Antarctica were able to forage throughout the colony, the majority of which was not defended by territorial skuas as in other Ross Island colonies. All local skuas were able to find enough food on the colony throughout January to support breeding and none were seen to forage at sea. Skuas foraged as individuals to obtain penguin eggs and chicks but kleptoparasitism usually occurred so that several skuas fed in turn on a single carcass. At the end of each feeding event a general melee occurred in which up to 30 skuas fought over the chick remains. The implications for skua breeding of this foraging regime, in which any skuas in the local area can obtain penguin food, are considered. We suggest that the high levels of food availability contributed to the unusually high success for this region of these skuas in raising both chicks. Desertion of chicks while foraging, however, leads to some mortality among older chicks later in the season through predation. It is recommended that further research on skuas at super-large penguin colonies be undertaken.

Double-brooding has not previously been recorded in the New Zealand Dotterel (Charadrius obscurus). Since 1994, we have recorded five definite cases of double- brooding in which both birds of the pair were colour-banded, two cases where banded females had unbanded mates, and several probable cases involving unbanded birds. In the five cases in which pairs were banded, females always re-nested with the same mate (monogamous double-brooding). We recorded one definite and one probable case of brood-overlap; in some other cases there was definitely no overlap. Predation, timing of laying, and individual variation are some of the factors that may determine whether double-brooding occurs in the New Zealand Dotterel.

Breeding Mohua (Yellowhead, Mohoua ochrocephala; Passeriformes) have been intensively monitored in the Eglinton Valley, Fiordland, since 1990. Birds were individually colour-banded and their territories mapped. Trapping and poisoning stoats (Mustela erminea) resulted in a large increase in Mohua numbers, but the population declined abruptly in winter 1996 following a period of unusually low temperatures. Details of the increase in numbers are presented and the reasons for the subsequent sharp population decline are discussed.