Tristan albatross  (Diomedea dabbenena)

The Tristan albatross is in grave danger of becoming extinct in the foreseeable future, with numbers having decreased by 28 percent over 46 years on Gough Island, disappeared almost entirely on Inaccessible Island and already become extinct on Tristan da Cunha. The dramatic decline in numbers on Inaccessible Island is attributed to predation by feral pigs (now absent) and humans, while the extinction on Tristan was probably the result of human exploitation, in addition to predation by rats. On Gough, storms have caused peat slips that have buried and killed nesting adults, although this is likely to be only a very rare occurrence (3). The main threat comes from bycatch from longline fisheries, with satellite tracking indicating a substantial overlap between the range of these birds and areas where longline fisheries are well known for their high rates of seabird bycatch mortality (3) (9). Further more, if one parent is lost at sea the other cannot cope with the food demands of their chick and the chick will most probably die. Astonishing recent research has also shown that invasive, introduced house mice, three times the size of those in Europe, are also devastating seabird populations on Gough Island by preying upon chicks (3) (10). The chicks are up to 250 times the weight of the mice but are largely immobile and defenceless, the species having evolved over millions of years on an island with no natural predators (10). Approximately 1,000 Tristan albatross chicks are thought to be killed each year by these seemingly unlikely predators (10). In fact, a recent survey has shown that, in 2008 the number of Tristan albatross chicks that have gone on to fledge is five times lower than it should be.

The Tristan albatross is listed on Annex 1 of the Agreement on the Conservation of Albatrosses and Petrels (ACAP), which seeks to coordinate activity to mitigate known threats to albatrosses. Gough and Inaccessible Island are nature reserves, and together form a World Heritage Site. Both islands are uninhabited, apart from a meteorological station on Gough. Satellite tracking monitors the dispersal of these birds, which helps provide information on the potential impact of longline fisheries. Educating fisheries about mitigation measures to reduce bycatch mortality is an ongoing conservation priority for all albatross species (3).

A study of the predatory mice conducted by The Royal Society for the Protection of Birds (RSPB) and funded by the UK government's Overseas Territories Environment Programme has shown that their eradication from the island is feasible. Unfortunately, however, until the conservation initiative receives adequate funding, the Tristan albatross will continue to be driven towards extinction (11). Gough Island is widely recognised as having one of the most diverse bird colonies in the world, including four endangered species, and every effort should therefore be made to protect it and the rich biodiversity it hosts (12).