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 subantarctic population of the fairy prion (Pachyptila turtur) was studied at South Georgia in 1982-83. Full measurements of breeding birds are given, together with details of breeding habitat, the timing of the main breeding cycle events, and chick growth (weight and wing, culmen and tarsus length). Regurgitated food samples showed the diet to be mainly Crustacea (96% by weight), fish and squid comprising the rest. Of crustaceans, Antarctic krill made up 38% of items and 80% by weight. Copepods (four species, mostly Rhincalanus gigas) made up 39% of items but only 4% by weight; amphipods [three species, principally Themisto gaudichaudii made up 22% of items and 16% by weight. Diet and frequency of chick feeding are compared with those of Antarctic prions and blue petrels at the same site; fairy prions are essentially intermediate.
Although the New Zealand fernbirds were long maintained in their own genus Bowdleria, some authors have recently submerged them in the Australasian genus Megalurus. The osteology of the fernbirds shows them to be very distinct, however, so that the genus Bowdleria is fully justified. The skull of Bowdleria is most similar to that of Amphilais (“Dromaeocercus“) seebohmi of Madagascar and these two species are similar in plumage and tail structure as well. A particularly close relationship between Bowdleria and Megalurus may thus be doubted. Bowdleria is characterized by reduced elements of the wing and pectoral girdle, and a strikingly modified pelvis combined with very robust hindlimb elements. This functional complex of the hindlimb is quite unlike any of the presumed close relatives of Bowdleria, but convergent similarities are identified in several other passerine groups. On the basis of plumage and osteology. Bowdleria rufescens of the Chatham Islands is a very distinct species from B. punctata.