Counting Adelie penguins at colonies: Seasonal and annual changes

Abstract

The number of Adelie penguin (Pygoscelis adeliae) adults at colonies around Syowa Station changes seasonally. The penguins started to arrive at the colonies on 20-25 October. The number of adults at each colony reached its maximum on 10-20 November, decreased until late November and was stable on 1-10 December. This seasonal pattern was consistent over years and colonies. Censuses in mid-November and early December are recommended since they could give reliable numbers of breeding pairs.