New censuses of a breeding population of Emperor penguin Aptenodytes forsteri at Snow Hill Island by ground and aerial photography techniques

LIBERTELLI M. M.; DONINI, G.; SOIBELZON, L.H.; DEL VALLE, R.A.; LUSKY, J.C.; PEDREIRA, D.; MOREIRA, M. E.; CORIA, N.R.

Auckland

Conferencia; SCAR XXXIII & OPEN SCIENCE CONFERENCE.; 2014

SCAR

During the last hundred years have been discovered new breeding colonies of emperor penguins. Snow Hill Emperor´s colony was discovered in the mid-nineties through an over flight at the area. Even today, new colonies are added to the already known, reaching a total of 46. Breeding colonies of A. forsteri are distributed around the Antarctic coastline between 64°S and 78°S during the winter season. This colony was located by GPS at 64° 30´S, 57° 26´W at the south coast of Snow Hill Island, a similar position reported by others authors in the past. This is the northernmost known Emperor penguin colony in the whole Antarctica.  Snow Hill colony, as most other emperor breeding colonies, is placed on the sea-ice pack about 40-50 m from the low ice cliffs. Although in general the colonies are found protected from prevailing strong winds by natural barriers like icebergs, but, when we visited this colony, in the winter of 2013, we did not find any significant icebergs circling the colony. There is growing concern about the future of some Antarctic species in view of the changes observed in recent years regarding the extent and thickness of the sea ice pack related to global warming. The Emperor penguin depends on sea-ice pack as a breeding platform during the winter-spring months also it is the molting habitat and the foraging environment. Actual climate models predict a decrease in this Antarctic penguin population as the result of the decline in sea-ice distribution. In the Antarctic Peninsula, where warming has been pronounced during last decades, the colony of emperor penguin at Dion Islands, Marguerite Bay, West of Antarctic Peninsula, became the first colony recorded as lost in the recent period of Antarctic regional warming. Meanwhile the colony counts performed on Snow Hill Island, located at a similar latitude, on the east side of the Antarctic Peninsula, resulted in 7012 and 7952 breeding pairs during the winter seasons of 2005 and 2013 respectively. Studies involving regular monitoring allow a determination of the fluctuation in Emperor´s breeding populations and obtaining long-term demographic dataset.  Our objective was to verify the location of the colony, to census the breeding population by aerial photography, to conduct a ground census of chicks and to obtain other useful information for the long term research project that we started at this colony.