The Impact of Man on Adélie Penguins at Cape Hallett, Antarctica

Summary

The joint US-NZ base at Cape Hallett, Antarctica, was established in December 1956 on a stony spit occupied by breeding Adélie penguins (Pygoscelis adeliae). Over the 16 years the base was occupied it expanded to cover 4.4 ha, roads were constructed, habitat modified and scientific studies conducted. The colony declined from 62 900 pairs by 1959 to 37 000 pairs in 1968, then may have increased to 50 000 pairs in 1972. We censused the colony annually since 1981 and made ground observations in 1983. These show that, while the population has increased to about its original size (over 66 000 pairs in 1987), few areas modified by man have been fully recolonized.

During human occupation subcolonies close to the station and roads decreased markedly but have now recovered. The greatest declines were in isolated sub-colonies subject to intensive banding and study, some of which declined to extinction and few of these have been re-inhabited.

During construction roads and the station environs were bulldozed flat so destroying the mounds on which the penguins nested. Even in the absence of people such areas were recolonized only where mounds remained, or where they were constructed when the base was demolished between 1984 and 1988.