Cool fact…
Both Heard Island and McDonald Island are volcanically active - they are Australia's only active volcanoes, and the only active volcanoes on subantarctic islands.

International significance

In addition to being recognised nationally for their conservation values, the Heard Island and McDonald Islands (HIMI) Territory and Marine Reserve are significant at an international level, not only as a World Heritage site, but as an important haven for migratory birds and seals and for their potentially globally important wetlands.

World heritage

The HIMI Territory, including the islands, adjacent offshore rocks and shoals and the territorial sea to 12 nautical miles, was added to the World Heritage List in 1997, with the following statement of significance:

HIMI is a unique wilderness, a place of spectacular beauty which contains outstanding examples of biological and physical processes continuing in an essentially undisturbed environment. Significant biological processes include colonisation and speciation, while the island group’s physical processes provide valuable indicators of the role of crustal plates in the formation of ocean basins and continents and of atmospheric and oceanic warming.

HIMI was considered to meet two of the natural criteria for listing as a World Heritage property, being both:

  • an outstanding example representing major stages of earth’s history, including the record of life, significant on-going geological processes in the development of land forms, or significant geomorphic or physiographic features; and
  • an outstanding example representing significant on-going ecological and biological processes in the evolution and development of terrestrial, fresh water, coastal and marine ecosystems and communities of plants and animals.

For more information about the HIMI World Heritage Area and its outstanding natural universal values go to the World Heritage pages in the Protection and Management section of this website. More information about other Australian World Heritage Areas is available on the World Heritage pages of the Department of the Environment, Heritage Water and the Arts website.

Migratory species

The HIMI Marine Reserve provides critical habitat for a number of birds and marine mammal specie, many of which are listed under international agreements for the protection and conservation of migratory species.

These agreements include:

Migratory bird species recorded as breeding in the Reserve include the wandering albatross, black-browed albatross, southern giant petrel, Wilson’s storm petrel and the light-mantled sooty albatross. Several species of cetaceans and non-breeding birds recorded in the Reserve are also listed under these international agreements.

See the Protection page in the Nature section of this website for a list of migratory species found in the Reserve and their conservation status.


Some areas of HIMI exhibit significant wetland features and processes, and provide habitat for a number of wetland species. These are the moist, low-level terrestrial, freshwater and shallow near-shore marine environments.

HIMI was rated as the most important Commonwealth-managed wetland in A Strategic Assessment of nationally important wetlands management by the Commonwealth, when assessed against criteria for wetlands of international importance as defined under the Convention on Wetlands of International Importance especially as Waterfowl Habitat (the Ramsar Convention). The Strategic Assessment found the HIMI wetland to satisfy six of the Ramsar criteria for wetlands of international importance.

A draft Ramsar Information Sheet (RIS) has been prepared and consideration is being given to nominating the Territory as a wetland of international importance. A summary of the qualities of the proposed wetlands site against the relevant criterion is given below:

  1. contains representative, rare or unique example of a natural or near-natural wetland type found within the appropriate biogeographic region.
    The islands are the only landmasses in the Kerguelen Province, defined using the Interim Marine and Coastal Regionalisation for Australia.
  2. supports vulnerable, endangered, or critically endangered species or threatened ecological communities.
    Heard Island’s wetlands support substantial populations of three species listed as threatened under the EPBC Act: the southern elephant seal (vulnerable), the southern giant petrel (endangered) and the Heard Island cormorant (vulnerable).
  3. supports populations of plant and/or animal species important for maintaining the biological diversity of a particular biogeographic region.
    Heard Island and McDonald Islands are the only land masses within the Kerguelen Province and therefore provide the only habitat for a range of wetland flora and fauna within the bioregion.
  4. supports plant and/or animal species at a critical stage in their life cycles, or provides refuge during adverse conditions.
    The HIMI wetland supports large breeding colonies of four species of penguin: macaroni, gentoo, king and southern rockhopper. The king penguin, which suffered major depredations early last century, is reported to be doubling its numbers on Heard Island every five years. The Heard Island shag and the Heard Island sheathbill (a shorebird) are subspecies endemic to HIMI. Heard Island is also a major moulting area for southern elephant seals.
  5. regularly supports 20 000 or more waterbirds.
    The HIMI wetland regularly supports more than four million waterbirds, with the majority being penguins. In particular, the macaroni penguin colonies on Heard Island and the McDonald Islands are estimated to total two million birds.
  6. regularly supports 1% of the individuals in a population of one species or subspecies of waterbird.
    The HIMI wetland supports the entire world population of the endemic subspecies of the Heard Island cormorant and the Heard Island sheathbill. The HIMI population remains the only sheathbills unaffected by introduced predators such as cats and rats. Gentoo penguins are believed to be present all year round, and the breeding population on Heard Island in 1987 comprised 16 600 pairs, representing approximately 6% of the global population. The macaroni penguin colonies are estimated to contain 2 million birds each, which represent approximately 21% of the world population.

More information on important Australian wetlands is available from the Wetlands pages of the Department of the Environment website.

This page was last updated on 1 July 2014.