Moult of the emperor penguin: travel, location, and habitat selection

All penguins except emperors Aptenodytes forsteri and Adelies Pygoscelis ad eliae moult on land, usually near the breeding colonies. These 2 Antarctic species typically moult some where in the pack-ice. Emperor penguins begin their moult in early summer when the pack-ice cover of the Antarctic Ocean is receding. The origin of the few moulting birds seen by observers on pass ing ships is unknown, and the locations are often far from any known coloni es. We attached satellite transmitters to 12 breeding adult A. forsteri fro m western Ross Sea colonies before they departed the colony for the last ti me before moulting. In addition, we surveyed some remote areas of the Wedde ll Sea north and east of some large colonies that are located along the sou thern and western borders of this sea. The tracked birds moved at a rate of nearly 50 km d(-1) for more than 1000 km over 30 d to reach areas of peren nially consistent pack-ice. Almost all birds traveled to the eastern Ross S ea and western Amundsen Sea. Sea-ice conditions were observed directly in t he Weddell Sea from ship and helicopter. Most flees selected for moulting w ere ridged, and usually >100 m(2). From these observations we predict where the most likely moult refuges are for emperor penguins from other colonies around the Antarctic continent.