Humpback whale. Photo AGAD

Cetaceans are any members of the group of marine mammals that includes whales, dolphins and porpoises.

Records around Heard Island and McDonald Islands (HIMI) are sparse due to a lack of opportunities to conduct surveys. However, areas of nutrient rich waters in the region are believed to provide suitable feeding grounds for a range of cetaceans.

The remains of seven species of cetacean have been found washed ashore at Heard Island. These include skulls of pilot whales, strap-toothed beaked whales, spectacled porpoises, Minke whales, hourglass dolphins, and southern bottlenose whales. Additional records exist of sperm whale bones and two dolphin heads found on Heard Island in early December 1929.

Several species of cetacean have also been observed at sea in the region, including blue whale, fin whale, killer whale, hourglass dolphin, strap-toothed beaked whale, spectacled porpoise, humpback whale, sperm whale, Minke whale, long-finned pilot whale, southern bottlenose whale, Commerson’s dolphin, dusky dolphin, Arnoux’s beaked whale and southern right whale.

Cetacean Conservation

Each of the above cetacean species is a listed cetacean under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and several are listed as threatened and/or migratory species. The Protection page in the Nature section has a table showing their conservation status and scientific names.

Under the EPBC Act recovery plans are in preparation for blue, fin, humpback and southern right whales. There is also an Action Plan for Australian Cetaceans.

The HIMI Marine Reserve lies within the Indian Ocean Whale Sanctuary, which was established under the International Convention for the Regulation of Whaling in 1979 to provide freedom from disturbance for migrating and breeding great whales in an area where whales were once hunted to the brink of extinction.