The sex of Addie penguins, Pygoscelis adeliae, may be determined by cloacal examination during the
early part of the breeding season. Later in the season it becomes increasingly difficult to determine the
sex of penguins by this method as the structures used for identification regress. Discriminant analysis
of morphometric characters has been suggested as an alternative. This technique was examined for
breeding birds of known sex near Mawson Station, Antarctica. The sex of 89% of breeding birds
could be correctly determined by comparing the discriminant score D = 0.582 Bl + 1.118 Bd + 0.219Fw,
where Bl is bill length, Bd is bill depth and Fw is flipper width, with a mean discriminant score (MDS)
of 55.39. In all, the sexes of 87% were correctly determined by means of length and depth only
(D=0.601Bl+ 1.154Bd, MDS=44.96). The sex of juvenile birds could not be determined. Determination
of sex by discriminant analysis is shown to give acceptable estimates of morphometric
characters divided by sex where only the mean and variance of these variables but not the sexual
identity of individual birds is required. Where absolute accuracy in sex determination is required,
80% of the birds in our samples would have to be discarded to be 90% confident of the sex of the
remainder.
A large number of squid, subsequently identified as Martialia hyadesi {Ornrnastrephidae) was stranded on beaches at the northern end of Macquarie Island, 54° 30'S, 158° 57'E, on 5 March 1971. The squid were immature, or at least pre-breeding, and had been feeding recently. It is suggested that a sudden change in wind direction, coupled with a rising tide, caused the stranding. This is the first reported stranding of this species, which has not previously been recorded in the Pacific region. THE STRANDING
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