Heard Island and McDonald Islands

Australia’s volcano

Heard Island and the McDonald Islands lie in the Southern Ocean at about 53°S, around 4,100 km south-west of Perth and 1,700 km north of Antarctica. The nearest land is France’s Kerguelen Islands, about 450 km to the north-west.^[2]

Heard Island is about 40 km long and 20 km wide. Most of it is Big Ben, an active volcano crowned by Mawson Peak, which at 2,745 m is the tallest mountain in Australian territory outside Antarctica.^[2][1] It is home to Australia’s only active volcano, and 12 major glaciers run down its slopes.^[4] They are shrinking: ice covered 80% of the island in the 1940s and around 64% in 2014.^[2]

The McDonald Islands are a group of rocky islets about 40 km west of Heard.^[1] Volcanic eruptions in the 1990s doubled the size of the main island and raised it higher, burying all its plants.^[2]

Sealers, then scientists

Bad weather and empty ocean kept the islands hidden for a long time.^[2] Britannica says a British sealing ship saw Heard Island in 1833; the Australian Antarctic Division says Europeans didn’t find the islands until 1853. The island is named after an American captain, John J. Heard.^[1][2]

The first recorded landing was in 1855.^[5] In the second half of the 19th century hunters exploited its elephant seal and penguin colonies, but since the early 1900s the island has been left alone.^[1] Scientists first came with HMS Challenger in 1874.^[5]

Britain handed the islands to Australia in 1947.^[1] Australia ran a station at Atlas Cove from 1947 to 1955. Since the first landing there have only been about 240 visits ashore on Heard Island, and only two landings on McDonald Island, in 1971 and 1980. Big Ben has been climbed three times: in 1965, 1983 and 1999/2000.^[5]

Untouched on purpose

UNESCO listed the islands as a World Heritage site in 1997.^[1] They are the only volcanically active sub-Antarctic islands, and no plants or animals have ever been brought there from elsewhere.^[6]

The surrounding marine reserve covers about 380,000 km² and was expanded from 24 January 2025, putting almost 90% of the exclusive economic zone under protection.^[2][4] Anyone who wants to go needs a permit.^[5] Australian boats have fished the zone for Patagonian toothfish and mackerel icefish since 1997, though not in its most protected parts.^[5]

A tariff on an empty island

When the United States announced its new tariffs on 2 April 2025, Heard Island and McDonald Islands were on the list, charged the same 10% as mainland Australia, even though an Australian government website describes them as “unoccupied by humans”.^[7]

Back after twenty years

In 2025 Australia’s icebreaker RSV Nuyina made two voyages to the islands: the first dedicated environmental visit to Heard Island in more than 20 years.^[4] Teams counted albatrosses, penguins and seals, checked them for H5 bird flu, and set up a weather station at Atlas Cove that sends data back to Australia in real time. They also took away 800 kg of rubbish and 300 kg of asbestos from the old station site.^[8]