Notornis, 38 (3), 233-238
Article Type: paper
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.