Heard Island and McDonald Islands (often referred to by the acronym HIMI) are a series of wild, barren, volcanic islands in the Antarctic Sea. Australian territories, these uninhabited islands are located close to two-thirds of the way from Madagascar to Antarctica.
The islands are uninhabited and are predominantly used for research, being the only sub-Antarctic islands that have active volcanoes, and also the only sub-Antarctic Islands with no known species introduced by humans.
Historically, they were used during the height of the sealing trade. The islands became a UNESCO World Heritage site in 1997.
The islands were discovered in the 1850s, and have been Australian territories since 1947.
The islands were used in the nineteenth century as a launching point for the global seal trade. Americans sealers lived on the islands at Oil Barrel Point, sometimes for a year or more, between 1855 and 1880. At its peak 200 sealers lived on the island, but by 1880 most of the islands’ seals had been wiped out and thus sealers lost interest in the island cluster.
It is thought that more than 100,000 barrels of elephant sea oil was produced from these islands.
The islands cover 372 square kilometers with over 100km in coastline, and are located within a 65,000 square kilometer marine reserve. They are an exposed part of the Kerguelen Plateau and include:
- Heard Island: an island whose mountains are mostly covered in glaciers; Mawson Peak is on the island – a 2745m high volcano which is part of the Big Ben massif; “Elephant” spit – 10km long –extends from the east of the island.
- McDonald Island, Flat Island, and Meyer Rock: small, rocky McDonalds Islands totaling 2.5 square kilometers are 44km west of Heard
- Black Rock, Shag Islet, Sail Rock, and Morgan Island: A few islets and exposed rocks north of Heard Island and totaling just over 1 square kilometer
The only two active volcanoes in Australian territory are on the islands. One volcano – Mawson Peak – is also Australia’s highest mountain. The other volcano on, McDonald Island, erupted in 1992 (and several times since, including most recently in 2005) after remaining dormant for 75,000 years. Recent volcanic activity has joined McDonald and Flat Islands, and approximately doubled the islands’ total landmass.
The islands have an Antarctic climate, with 70% of the Heard Island landmass permanently covered by snow or ice: low seasonal and daily temperatures, low and persistent cloud cover, frequent precipitation (rain or snow on average three out of every four days), strong winds. At Atlas Cove (northwestern edge of Heard Island), temperatures range from zero to four degrees Celsius, or three to five degrees in summer and minus one to one degree in winter.
The plant life is predominantly tundra – grasses, mosses, and lichens. The islands’ animals include ocean seabirds, penguins (with the world’s largest macaroni penguin colony), and seals – including fur and leopard seals.
Heard Island is very steep, which – when combined with high levels of precipitation – results in very fast-moving glaciers. Glaciers advance almost 250 metres a year.
Activities (Nature and Wildlife Interest)
Heard Island is almost exclusively used for research purposes, and is visited very infrequently – with perhaps two or three authorized landings a year of several hours each.
Occasionally there are other unofficial visits.
There are no permanent visitor facilities, however there is potential for extreme private travel – Antarctic mountaineering or ecotourism.
There is no permanent human habitation on the island, nor are there facilities for accommodation or visitors.
The islands are not located close to any other islands: they are situated 4099km southwest of Perth, 3845km southwest of Cape Leeuwin, Australia, 4200km southeast of South Africa, 3830km southeast of Madagascar, and 1630km of Antarctica.
The islands have no ports or harbours, and as such, ships must anchor offshore. Island access is by helicopter, amphibious vessel, or rubber boats.