Two wind-lashed specks in the southern Indian Ocean—Marion Island and the smaller Prince Edward Island—make up South Africa’s only sub-Antarctic territory. Lying roughly 1,900–2,000 km southeast of the mainland, they’re volcanic, treeless, and vital to Southern Ocean science and conservation. Encyclopedia Britannicarsis.ramsar.org
What—and where—they are
Marion is the larger island, crowned by Mascarin Peak (≈1,230 m). Prince Edward, 19 km to the north-east, rises to about 670 m. The pair are sub-Antarctic tundra: sodden bogs, mosses, grasses and lava hills under near-constant westerlies and frequent rain or snow. France’s Marion du Fresne charted them in 1772; James Cook later named them after Prince Edward (the future Duke of Kent). South Africa annexed the islands in 1948 and has maintained a research and weather station on Marion ever since. BirdLife DataZoneEncyclopedia BritannicaWikipedia
A wildlife stronghold
The islands are among the world’s most important breeding sites for seabirds and seals. They host one of the largest concentrations of Wandering Albatrosses—about 40–45% of the global population—along with Indian Yellow-nosed, Grey-headed and Sooty/Light-mantled albatrosses. Four penguin species breed here: King, Macaroni, Southern Rockhopper and Gentoo. Southern Elephant Seals and Sub-Antarctic Fur Seals also haul out in big numbers. The archipelago is a BirdLife Important Bird Area and a Ramsar Wetland of International Importance. acap.aq+1speciesstatus.sanbi.orgTaylor & Francis Onlinersis.ramsar.org
Protected ocean, protected islands
In 2013 South Africa declared the surrounding waters the Prince Edward Islands Marine Protected Area—its first offshore MPA. The zoning includes a 12-nautical-mile no-take sanctuary around the islands and additional restricted/controlled zones aimed at safeguarding foraging grounds for seals, whales and seabirds (and managing Patagonian toothfish pressure). On land, the islands are a Special Nature Reserve under South African law. gov.zawwfeu.awsassets.panda.orgWikipedia
Science on the edge of the Roaring Forties
Marion Island doubles as a living laboratory. Long-running studies track climate, ocean ecology, volcanism and wildlife dynamics, with a modern SANAP research base (rebuilt 2001–2011) supporting year-round teams. Volcanically, Marion is still active: the last confirmed eruption was noted in 1980; a small event was also reported in 2004. Wikipediavolcano.si.eduearthobservatory.nasa.gov
The conservation challenge: mice
House mice, introduced historically to Marion, now prey on invertebrates and seabirds—including live albatrosses—exacerbated by a warming, drier climate. The Mouse-Free Marion project (a partnership with South Africa’s environment department and BirdLife South Africa) is planning a large-scale aerial baiting eradication modeled on successful sub-Antarctic efforts; success could prevent local extinction risk for many of the island’s 29 breeding bird species. acap.aqThe GuardianMouse Free Marion
Visiting (short answer: you can’t)
Tourism is prohibited. Access is tightly restricted to research and logistics—typically via the South African polar supply ship S.A. Agulhas II with helicopter transfers to the Marion base. Prince Edward Island is visited only at long intervals by small research teams to keep it near-pristine. On rare occasions, offshore “no-landing” birding cruises have sailed past the islands for pelagic viewing (e.g., BirdLife South Africa’s Flock to Marion voyage in 2022).
Marion Island Marine Mammal ProgrammeMinisterie van LNVMouse Free MarionBirdLife South Africa
Why they matter: The Prince Edward Islands give South Africa a front-row seat on the Southern Ocean—crucial for understanding climate, fisheries, and the life cycles of iconic seabirds. In a world where intact ecosystems are rare, these bleak, beautiful islands are both sanctuary and signal—worth every ounce of protection they receive
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