The Flag of Heard Island and McDonald Islands

Heard Island and McDonald Islands has no flag of its own. The flag shown for it is the Australian National Flag: a blue field with the Union Jack in the upper hoist corner, a large white seven-pointed Commonwealth Star beneath it, and the five white stars of the Southern Cross on the fly. The islands are an Australian external territory, so the national flag is the one that applies. Nobody lives on them. The flag stands for sovereignty, not for a community.

Heard Island and McDonald Islands is a volcanic outpost in the southern Indian Ocean, about 4,000 km south-west of mainland Australia. Nobody lives there, and no local flag has been adopted. The Australian National Flag stands in for the territory. It is a flag of ownership, raised on a place with seals, penguins and an active volcano.

A flag borrowed from the mainland

The territory has no flag of its own. Flags of the World says so plainly: because this is an Australian external territory, the Australian flag is used. A contributor to that site adds that the blue flag is flown there "if anything," which fits a place with no town, no government building and no regular visitors.

That makes this page a cousin of the Bouvet Island entry. In both cases a distant government holds the land, and the flag of the holder does the job.

The Australian flag is a defaced Blue Ensign. A Union Jack fills the upper hoist corner. Below it sits the seven-pointed Commonwealth Star. The Southern Cross takes the fly: four larger seven-pointed stars and one smaller five-pointed star. The proportions are 1:2.

Where Australian law reaches

The legal link is short. The Heard Island and McDonald Islands Act 1953 is Act No. 7 of 1953. Its long title is "An Act to provide for the Government of Heard Island and McDonald Islands." The register of legislation dates the as-made text to 27 March 1953.

The Australian Antarctic Division says the Act confirms Australia's sovereignty over a territory transferred from the United Kingdom. It applies Commonwealth laws that expressly cover the territory, plus certain Australian Capital Territory laws and Jervis Bay Territory criminal laws. The Governor-General makes ordinances for the islands. If an ordinance conflicts with one of those other laws, the ordinance wins.

The flag has its own statute. The Flags Act 1953, assented to on 14 February 1954, declares "the blue flag" described in its schedule to be the Australian National Flag. The Act says it extends to all the Territories of the Commonwealth. Heard Island and McDonald Islands is one of them.

From sealers to scientists

John Heard, an American captain, made the first confirmed sighting of Heard Island on 25 November 1853. Wikipedia puts the sighting of the McDonald Islands in 1854, by William McDonald. American sealers worked the islands from 1855 to 1882, according to Flags of the World, and the hunt nearly wiped out the seal population.

Britain formally claimed the islands in 1910. In December 1947 an Australian party under Stuart Campbell landed at Atlas Cove and set up a research station. It closed in 1955.

The legal handover followed the landing. Britain and Australia exchanged notes on 19 December 1950, and the transfer took effect from December 1947. Wikipedia and Flags of the World agree on the 1950 exchange.

A volcano and a reserve

Heard Island is dominated by Big Ben, a stratovolcano about 2,745 m high. Its summit cone, Mawson Peak, is the highest point in Australian territory outside the Australian Antarctic Territory. The territory holds Australia's only active volcanoes.

The islands were inscribed as a World Heritage Site in 1997. Wikipedia dates the marine reserve to October 2002, and it covers about 380,000 km². Southern elephant seals are the most common mammal on Heard Island, and Antarctic fur seals breed there in significant numbers. Patagonian toothfish is the main commercial fishing target in the surrounding waters.

Wildlife is also the main worry now. Wikipedia reports that H5N1 bird flu reached elephant seals in the summer of 2025 and 2026, with more than 13,000 pups believed dead. The Australian Antarctic Program made its first visit in decades in October 2025 and reported findings on the outbreak in June 2026.

Who gets ashore

Nobody lives on the islands, so visits are rare and controlled. The Environment Protection and Management Ordinance 1987 requires a permit to enter the territory and a second permit for any activity that threatens the environment or native species. The Weapons Ordinance 2001 limits weapons to approved scientific projects.

References

[1] "Heard Island and McDonald Islands," Wikipedia. https://en.wikipedia.org/wiki/Heard_Island_and_McDonald_Islands

[2] "Heard Island and McDonald Islands," Flags of the World. https://www.crwflags.com/Fotw/Flags/hm.html

[3] "Territory legislation," Australian Antarctic Division. https://www.antarctica.gov.au/antarctic-operations/stations/other-locations/heard-island/protection-and-management/legislation/territory-legislation/

[4] "Heard Island," Australian Antarctic Division. https://www.antarctica.gov.au/antarctic-operations/stations/other-locations/heard-island/

[5] "History of Heard Island," Australian Antarctic Division. https://www.antarctica.gov.au/antarctic-operations/stations/other-locations/heard-island/history/

[6] Flags Act 1953 (Act No. 1 of 1954), Federal Register of Legislation. https://www.legislation.gov.au/C1954A00001/2008-07-04/2008-07-04/text/original/epub/OEBPS/document_1/document_1.html

[7] Heard Island and McDonald Islands Act 1953 (Act No. 7 of 1953), Federal Register of Legislation. https://www.legislation.gov.au/C1953A00007/asmade/text

[8] "Flag of Australia," Wikipedia. https://en.wikipedia.org/wiki/Flag_of_Australia