The waters of the Tristan da Cunha archipelago cover a vast area in the South Atlantic Ocean close to three times the size of the United Kingdom’s mainland, with an exclusive economic zone (EEZ) of 754,000 square kilometres (291,121 square miles).
Four islands make up the chain: Nightingale, Tristan, Gough, and Inaccessible. The latter two are collectively recognised as a UNESCO World Heritage Site. The marine ecosystem surrounding the islands remains healthy and vitally important for albatrosses, penguins, and seals. The remote location of this United Kingdom Overseas Territory – midway between Argentina and South Africa – means that many of these species are found nowhere else on Earth.
Ecological significance
Tristan da Cunha serves as the breeding ground for more than 85 percent of the world’s endangered northern rockhopper penguins. The species, known locally as “Pinnamin,” live alongside subantarctic fur seals and a single breeding colony of southern elephant seals. Seal populations are slowly recovering from the unsustainable hunting practices of the late 18th and early 19th centuries.
Two endangered birds – the sooty albatross (“Peeeoo”) and the Atlantic yellow-nosed albatross (“Molly”) – breed only in the Tristan da Cunha archipelago. According to the IUCN Red List of Threatened Species, critically endangered Tristan (“Gony”) albatrosses breed almost exclusively on Gough, as do endangered Atlantic petrels. With a recorded wingspan up to 118 cm (47 inches), spectacled petrels, also considered vulnerable, reproduce only on Inaccessible. The same island also provides a home for an endemic species of land bird, Inaccessible rails, which are the smallest flightless bird in the world and considered vulnerable.
On November 13, 2020, the Tristan da Cunha Island Council committed to designate most of the archipelago’s exclusive economic zone (EEZ) as a marine protection zone. The move will fully safeguard an area that spans more than 687,000 square kilometres (265,000 square miles), about 91% of the waters of the remote South Atlantic Ocean island chain, and create the fourth-largest fully protected marine reserve on the planet. Final action on the necessary legislation is expected in 2021.