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The red-footed booby (Sula sula) colony on Mabualau Island, Fiji, was visited from 1980 to 1982. Eggs were recorded throughout the year, and young were found in seven of the nine months of the year considered. The two peaks of nesting recorded were about 7-8 months apart. Only unsuccessful birds were likely to nest twice in the same year. Fledging success was low in both 1980 (55%) and 1981 (24%). Climatic factors rather than food supply or predators caused most mortality. The diet comprised flying fish and squid. Growth was similar to that on Aldabra Atoll, but fledging weight was higher. The timing of the breeding seasons is discussed.

The breeding of the Chatham Island warbler (Gerygone albofrontata) was studied over five seasons on three islands in the Chatham Island Group. The breeding season is short, and only one brood is raised per year. On predator-free ‘petrel islands’, nests were low to the ground in dense vegetation, whereas on Chatham Island nests were high and in the open. Mean clutch size was 3.1 eggs (n=79). Incubation and nestling periods were both about 20 days. Density of breeding birds was highest in regenerating forest clumps on predator-free islands, with about 10 pairs per hectare. Comparisons are made with the breeding biology of the grey warbler (G. igata) of the New Zealand mainland and with other Gerygone species. Brood parasitism by the shining cuckoo (Chrysococcyx lucidus) and how vulnerable the Chatham Island warbler is to extinction are discussed.

Grey warblers (Gerygone igata) at Kowhai Bush, Kaikoura, apparently moulted once annually – between January and March. They nested in 19 kinds of trees and shrubs – mostly small-leaved species, especially kanuka, the dominant plant in the study area. Behaviour associated with selection of the nest site is described. A list of materials used in building is given. On average, nests were 14 cm long and just over 7 cm wide. Nearly half the nests hung freely from their upper attachment; others also had attachments laterally and below. The entrances of nests were non-randomly orientated in 1976 but not so as to face away from prevailing winds. Copulation is described. Three eggs in September were laid close to sunrise. Late eggs were wider on average than early ones but no different in length. The constant that related fresh weight of eggs, length, and the square of width was 0.598. Eggs lost about a quarter of their weight during incubation. Grey warblers hatched with natal down distributed in eight main and two minor patches. The physical and behavioural development of nestlings is described. A sample of 19 nestlings had been fed invertebrates of six orders. Caterpillars occurred in 90% of stomachs and made up 42% of ingested items. Spiders were next most important of total items. Nestlings were parasitised by the blood-sucking mite Ornithonyssus bursa. Fledglings had distinctive dark brown irides and yellowish facial plumage until February-March, when they moulted to adult form. Males played the greater role in caring for early fledglings while the female built the late nest. Young males seemed rarely to be successful in holding territory the summer after that in which they were reared. Brood parasitism by shining cuckoos was the main cause of failure of late eggs (though a relatively minor factor overall); mammalian predation was the greatest single cause of nestling mortality.

The breeding of the South Island robin at Kowhai Bush, Kaikoura, during the 1977-78 and 1978-79 seasons and the mortality from August 1976 to December 1979 are described. Most robins began laying in August and completed breeding in January. Thirty-four percent of their nests were relined “old” ones built in previous seasons by robins or Turdus species. Average time to build a “new” nest was 3.4 days, followed by a prelay period that averaged 4.2 days. Eggs were laid at about 24-hour intervals. Mean clutch size was 2.7 eggs (range 2-4), being smallest in July and largest in October. Incubation averaged 17.7 days, and the females spent 81% of daylight time on the eggs; males did not incubate. In the two seasons, 63% of the eggs hatched and 23% were eaten by predators. Hatching success varied between seasons, months and the four age classes of females. Both parents fed the nestlings, but only the female brooded. Nestlings averaged 20.8 days in the nest, with little or no brooding after day 15. Overall, 42% of the nestlings fledged; most of the rest were eaten by predators. The proportion that fledged decreased as the season progressed because the loss to predators increased. Pairs fledged a mean of 2.1 fledglings in 1977-78 and 2.9 in 1978-79. Juveniles were fed by their parents from 24 to about 50 days, depending on the number of juveniles, how many the female cared for and how soon the next clutch hatched. Mortality was highest in summer for immatures and autumn for adults. Immatures died more in summer, possibly because they were less efficient foragers than adults, but similar proportions of the two age classes died in autumn and winter, perhaps because predation was the main mortality factor.

Regular and closely spaced counts of migratory waders were made at Suva Point, Fiji, over 15 months. Arrival and departure times were determined with fair accuracy for the four main species: wandering tattler (late August-early May); least golden plover (early September-early April); turnstone (late September-late April) and eastern bar-tailed godwit (late September-early April). Comparisons with earlier counts in 1961/2 and 1969/70 show a large increase in the summering godwit population and perhaps a reduction in the number of wandering tattler.