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

All penguins except emperors Aptenodytes forsteri and Adelies Pygoscelis adeliae 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 passing ships is unknown, and the locations are often far from any known colonies. We attached satellite transmitters to 12 breeding adult A. forsteri from western Ross Sea colonies before they departed the colony for the last time before moulting. In addition, we surveyed some remote areas of the Weddell Sea north and east of some large colonies that are located along the southern 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 perennially consistent pack-ice. Almost all birds traveled to the eastern Ross Sea and western Amundsen Sea. Sea-ice conditions were observed directly in the Weddell Sea from ship and helicopter. Most flees selected for moulting were 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.