The gentoo penguin population has fallen from about 116,000 pairs to about 65,000 pairs - a decline of about 43 per cent. Rockhopper penguin numbers meanwhile dropped from 3,169,000 pairs to around 300,000 pairs - a decline of about 90 per cent.
Recent monitoring suggests that the declines in both species are continuing.
The news is particularly bad for the rockhopper as the remaining Falklands population represents the world's most important breeding site for the species. This according to a study in Oryx , the journal of the Fauna and Flora Preservation Society in England. The fourth main Falklands penguin, the Magelannic, was not included in the census because of the difficulties associated with counting a species that nests in burrows. Bingham, M. 1998. The distribution, abundance and population trends of gentoo, rockhopper and king penguins in the Falkland Islands.