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The Pukeko, or Purple swamphen (Porphyrio porphyrio melanotus), has monomorphic plumage, which makes sexing of the living bird difficult. A method of sexing using body measurements has been proposed (Williams & Miers 1958), but it uses measurements and cut-off values which are not fully reliable. While cut-off values may vary geographically, the reliability of the different measurements should not. This paper uses multivariate techniques to investigate the reliability of combinations of measurements for sexing swamphens and outlines the problems with the existing method.

“Waterfowl: ducks, geese and swans of the world” by Frank S. Todd. Sea-World Press. Harcourt, Brace, Jovanovich, New York and London.

Obituary, pages 179 to 186. Bibliography, pages 187 to 195.

Records were kept of seabirds seen during 30 watches, totalling about 45 hours, on a voyage from Sydney to Buenos Aires via New Zealand and the Straits of Magellan.  Results are presented in the form of an annotated species list.  Passage movements of Puffinus griseus and Pterodroma lessonii were observed, and records of Pterodroma axillaris, P. inexpectata, Pufinus bulleri and P. puffinus appear to be of distributional significance.  A probable sight record of Pterodroma magentae is discussed in detail.

Between 8 November and 4 December 1978 observations were made on Southern Great Skuas (Stercorarius skua lonnbergi) at Antipodes Island in the Southern Ocean. Their food habits were determined by observing birds and identifying prey remains. Penguin eggs and chicks were the dominant prey of coastal skuas, whereas those with inland territories relied on petrels and shearwaters. Clutch size in 11 nests averaged 1.8 eggs; most eggs in nine study nests hatched during the first fortnight of November. Hatching success was 54%, but only 3 of 10 chicks survived until 4 December. At that stage of the breeding season, and allowing for unnatural losses of eggs and chicks, productivity was 0.5 chicks per breeding pair. Six chicks were weighed and measured for 5-20 days. Hatching weight averaged 74.3 g. Initial weight gains were small, but after day 4 the average growth rate was 31.6 g/day. Chicks which were heavier at hatching remained so subsequently. Mean bill length at hatching was 17.8 mm and mean depth 9.9 mm. Little growth occurred for the first five days, but afterwards the average growth rate was 1.0 mm/day for bill length and 0.4 mm/day for bill depth. The ratio of bill length to depth changed during growth, and attained the adult condition by age 17-20 days. There were no consistent differences between chicks from coastal and inland nests in their weight gains, or in the growth of their bills.

Contributors: Stanely Cramp (chief editor), K. E. L. Simmons, I. J . Ferguson-Lees, R. Gillmor, P. A. D. Hollom, R. Hudson, E. M. Nicholson, M. A. Ogilvie, P. J. S. Olney, K. H. Voous, J. Wattel. Volume 1: Ostrich to Ducks. 722 pp. 108 col. pl. Oxford University Press 1977.