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An estimate of the breeding population of royal albatrosses (Diomedea epomophora sanfordi) on the eastern islet of The Sisters group of the Chatham Islands in January 1954 was between 400 and 450 birds. In October 1964 the breeding birds were considered to be occupying only one-quarter of the area as seen in January and the count of birds was accordingly multiplied by four giving a theoretical peak breeding population of 360 pairs. Similarly, Buller’s mollymawk (D. bulleri) at the corresponding dates in 1954 and 1964 was considered to have a breeding population of 250 and 240 pairs respectively. A preliminary count from RNZAF aerial photographs (fide C.J.R. Robertson) indicated the presence of 630 pairs of royal albatrosses on the eastern Sister at the end of November 1973, and more detailed results are expected from current field studies. At The Pyramid, a southern outlier of the Chatham Islands, counts of birds along strips of rock faces suggested a total population for the Chatham Island mollymawk (D. cauta eremita) of 2,500 pairs, a figure comparing favourably with earlier estimates of “several thousand” and “between two and three thousand” pairs.

Based on all the information from visits made up to 1969, tentative timetables have been drawn up for the breeding cycles of the Chatham Islands populations of the royal albatross and Buller’s mollymawk, both of which also breed elsewhere, and of the Chatham Island mollymawk which is known to breed only on The Pyramid.

Egg-and-chick survival frequency in the yellow-eyed penguin was followed for nineteen nests in three breeding areas on the Otago Peninsula. Observations were made through the tenth post-hatching week for each nest. Survival rate was substantially worse than that reported by Richdale in 1957. There were also differences in survival rate among the three breeding areas within the sample. It is suggested that human and farm-animal activity is responsible for the relatively poor survival rates.

Head and neck anatomy in the wrybill (Anarhynchus frontalis) are described from a spirit specimen and a skeleton. In most respects, the wrybill closely resembles plovers of the genus Charadrius. Careful examination has failed to reveal any asymmetry other than that of the bill. Apart from the bill shape, and a gape situated unusually far forward, the main peculiarity of the wrybill is a bony bridge between the two ventral bars of the upper jaw, mentioned by Lowe (1931). The significance of this structure in relation to bill asymmetry is discussed. An analysis of the stomach contents of the spirit specimen is given.

The crested grebe Podiceps cristatus australis is a rare bird in New Zealand, now confined to the South Island. It was formerly present on a few of the large North Island lakes; there is a subfossil record from a Maori midden, carbondated to A.D. 945, and more recent observations – from the period 1870–1900 of breeding populations on Lakes Waikareiti and Waikaremoana. In Nelson-Marlborough crested grebes were formerly found on Lakes Rotoroa and Rotoiti; they were possibly first seen in New Zealand and identified on Lake Rotoroa in 1846 by Heaphy, and certainly observed and correctly identified at these lakes by Haast in 1860. They have disappeared as breeding birds from the lakes some time during the last 15–20 years. There is a sub-fossil grebe from Lake Grassmere, Marlborough, possibly from a Maori midden. Today there are no longer crested grebes in the North Island or in Nelson-Marlborough, northern South Island.