Although Heard Island, with its glaciers and rocky coastline, is pretty far from most people's idea of a wetland, a wetland it is.
Or more accurately, Heard Island has a number of moist, low-level terrestrial, freshwater and shallow near-shore marine environments (wetlands) scattered around its coastal perimeter.
These wetlands areas are of high conservation significance. They exhibit significant wetland features and processes and provide critical breeding and feeding habitat for a number of animals considered to be wetland species, including southern elephant seals and macaroni, gentoo, king and southern rockhopper penguins.
Six wetland types have been identified at Heard Island, covering a total area of approximately 1860 hectares:
- Coastal ‘pool complex’ (237 ha)
- Inland ‘pool complex’ (105 ha)
- Vegetated seeps mostly on recent glaciated areas (18 ha)
- Glacial lagoons (1103 ha)
- Non-glacial lagoons (97 ha)
- Elephant Spit (300 ha)
Some wetland areas have been recorded on McDonald Island but, due to substantial volcanic activity since the last landing was made their in 1980, their present extent is unknown.
The Heard Island and McDonald Islands (HIMI) wetland is listed on the Directory of Important Wetlands in Australia and, in a recent analysis of Commonwealth-managed wetlands, was ranked highest for nomination under the Convention on Wetlands of International Importance Especially as Waterfowl Habitat (Ramsar Convention). The analysis found that the HIMI wetland satisfy six of the Ramsar criteria for wetlands of international importance. A nomination is currently under consideration.