Long-term population changes of Adelie, chinstrap, and gentoo penguins in the regions of SSSI No.8 and SSSI No.34, King George Island, Antarctica

Abstract

Population estimates of Adelie, chinstrap, and gentoo penguins were obtained at the SSSI No. 8 during 1990,1992, and between 1994 and 1996, and at the SSSI No. 34 between 1994 and 1996. The most numerous species at both localities were the Adelie penguin popula­ tion, which appears to be fairly stable in the region of SSSI No. 8, oscillating at the level of 17 000 nests. However, in the region SSSI No. 34 the Adelie population decreased. The gentoo penguin population doubled in the region of SSSI No. 34 since 1980, but decreased in the region of SSSI No. 8. Significant decreases in chinstrap nest numbers in both sites were found during the study period. This pattern mirrors the general pattern of the Pygoscelis penguin population changes in the Antarctic Peninsula region. There is increasing concern that tourism and other hu­ man-related activities may negatively impact penguin populations. However, our data are insuf­ ficient to prove that hypothesis.