Not many South Africans know that our country has overseas possessions. They are Marion and Prince Edward Islands in the Southern Ocean, 2 200km south-east of Cape Town. Completely uninhabited – save for a weather and research station on the larger Marion Island – the two sub-Antarctic islands are cold, windy, wet and inhospitable to humans. In marked contrast they are home to millions of seabirds and seals. Among this teeming life are thousands of albatrosses, some of which may be seen on birding tours out of Cape Town. John Cooper and Robyn Adams, of the Mouse-Free Marion Project, write about the islands’ albatrosses and the threats they face on Marion from diminutive House Mice.