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A survey of Banded Dotterel on Adams, Enderby, Ewing, Rose and part of the main Auckland Island was made in November 1989. Nesting was recorded for the first time on Enderby Island (8 nests) and 11 nests were found on Adams Island. The behaviour of dotterels on both islands indicated the presence of many more nests. Some dotterels moved at night from fellfield and moorland breeding grounds to the beaches of Adams, Rose and Ewing Islands. A total of 730 birds was counted, most on Enderby Island (440) and Adams Island (273). Previously, the total was considered to be 100-200 birds. Our high count is probably the result of an increase in breeding habitat following drastic vegetation modification by fire and introduced mammals on Enderby Island during the 19th century. The population has probably been rising for at least 20 years, but this has been overlooked because there has been no previous opportunity to count dotterels during their breeding season, when they are sedentary.

The first known breeding of the Black-winged Petrel (Pterodroma nigripennis) on Mangere Island was studied in 1987-88 from the pre-laying period to part way through the chick rearing period. The first returning bird was noted on 30 November; eight incubated eggs were found, calculated to have been laid in mid-January. The eggs hatched in late February – early March; fledglings were calculated to have left in late May. The breeding cycle was about 2 weeks later than at more northerly breeding sites. The approximate mean incubation shift was 13.5 days. The colours of chicks are described in detail. Only two of the five chicks that hatched were still alive by the end of the study. Interference at the nest site by other petrel species apparently caused some nesting failures. No birds were found undergoing active wing or tail moult. The brood patches of most adults examined were largely bare in late January and February and were refeathering in March. The birds were active only at night.

We assessed the utility of morphometric characters for identifying the sex of adult Fiordland Crested Penguins (Eudyptes pachyrhynchus) on the Open Bay Islands. Penguins that gave ecstatic calls at nest sites during the courtship period were designated as males; their companions at nest sites were designated as females. Measurements of culmen length, foot length and weight showed overlap between sexes, but bill depth and a bill index (culmen length x bill depth) did not. The bill depth and bill index of penguins of unknown sex fell on either side of the zone of non-overlap between sexes. Although the specific criteria for determining sex vary between populations of Fiordland Crested Penguins, measures of bill size appear to be the best criteria in this and other species of penguin.

A post-breeding flock of New Zealand Dotterels was monitored for 3.5 years at a site on the east coast of Northland, New Zealand. The pattern of flocking and dispersal was the same each year; the flock began to form in January and was at peak numbers in February and March. Birds began to return to their breeding grounds in late March, and two-thirds of those that bred away from the flock site had left by the end of April. Individual colour- banding showed a very high degree of breeding-site and flock-site fidelity. All the adults in the flock bred within a 16 km radius (the central study area) and none was found outside this area during the study. All adults in the central study area visited the flock each year; however, at two other localities in the greater study area a few birds were entirely sedentary on their breeding grounds and did not visit a flock. Breeding territories of birds resident at the flock site changed little between seasons. Unlike many migratory members of the genus Charadrius, NZ Dotterels of the northern population showed very high mate-retention from one season to the next, with both members of a pair usually occupying their territory for much of the year.