South Polar Skua Population Census

Skuas and Adélie penguins (Pygoscelis adeliae) both prey heavily on Antarctic silverfish (Plueragramma antarcticum) and krill (Euphausia crystallorophias and E. superba) and overlap in breeding space during the summer in this region, though not entirely.

If we make the assumption that physical (e.g. persistent sea-ice cover) and biological (e.g. prey abundance) conditions, in the absence of other factors, affect population dynamics and growth of both seabird species’, then similar trajectories for each population could emerge. On the other hand, in McMurdo Sound, and especially along the Victoria Land Coast, appreciable numbers of skuas nest where there are no penguins.