Changes in size of the Hope Bay Adélie penguin rookery as inferred from Lake Boeckella sediment

Abstract

Concentrations of phosphorus and copper in the sediments of Lake Boeckella (Antarctic peninsula) were used to provide an estimate of the size of the Adélie penguin rookery Pygocetis adeliae Based on dated subsamples from a sediment core, I conclude that penguins have been present in Hope Bay since 5550 BP, with the exception of a short penod around 5300 BP Their influence on the lake sediment reached a maximum at c 40 BP and has drastically declined since then The rookery started to grow between 850 and 1250 BP due to a climate deterioration The increased amount of food (mainly krill), caused by extensive fur seal hunting in the nineteenth century was probably not enough to affect rookery growth However, the drastic decline m whale stock in the 1930's and 1940's and the subsequent increase m krill abundance may have enhanced rookery growth The increasing disturbance by man in Hope Bay seems only to have changed the shape of the rookery and the penguins paths to the sea, but not to have stopped the growth of the rookery