A small breeding colony of Northern Buller’s Mollymawks (Diomedea bulleri platei Reichenow, 1898) is recorded from the Three Kings Islands off northern New Zealand. The subspecies was previously known to breed only at the Chatham Islands, which lie 10 degrees of latitude south of the Three Kings.
Vocalisations of the North Island Brown Kiwi (Apteryx australis mantelli) were monitored from March 1981 to July 1982 in Waitangi State Forest, Northland. Calling rates were found to be seasonally cyclic and correlated with breeding. Males calIed more often than females. Four categories of kiwi sounds are described and their possible functions discussed. A census of kiwis based on counts of calls underestimates the population: a banding study in a small area gives a much better indication of kiwi numbers. An estimated 800-1,000 kiwis inhabit Waitangi State Forest. Calling rates are density dependent and so can be used for comparison of kiwi population densities between two areas.
In Canterbury, Caspian Terns (Hydroprogne caspia) nest mainly as single pairs associated with colonies of Black-backed Gulls (Larus dominicanus) on shingle riverbeds. Of 37 nests studied, 28 (75%) hatched and 20 (54%) produced a total of 21 flying young, each pair raising an average of 0.6 young per season. The low productivity is attributed to reduced prey availability.
In the 1982/83 season 13 adults of the Black-fronted Dotterel were again found on the Manuherikia riverbed near Alexandra, the same number as in the previous season. Details of breeding case-histories for five pairs are given. Breeding success was very low because of predation and atypical persistent flooding throughout the season – which was also a very extended one, lasting from territorial occupancy in October to final fledging in April. The incubation period is not less than 23 days and is likely to average about 26. Some details of eggs, nests and territories, as well as some aspects of behaviour, are described.
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 measurements of male and female Brown Creepers (Finschia novaeseelandiae) were compared to determine whether they are sexually dimorphic and, if so, which characters can be used to distinguish the sexes. In all the measured characters males were significantly larger than females. Possible selective advantages of the Brown Creeper’s sexual dimorphism are discussed. Wing length was found to be the most reliable discriminator of sex.