False killer whales off the Northern Australia coast need their conservation status reviewed because of similarities they share with groups from Hawaii listed as Endangered in the USA, a Charles Darwin University (CDU) researcher says.
The latest research, published in Frontiers in Marine Science, investigated satellite information and DNA samples of the marine mammals in shallow coastal waters from the Cobourg Peninsula in the Northern Territory to the Kimberley region of Western Australia.
In 2012 one of the false killer whales sampled within Port Essington of the Cobourg Marine Park in northern Australia was found to share genetic ancestry with animals found off the coast of Hawaii, and there are other similarities between the groups too.
In Hawaii there are two separate groups of coastal false killer whales - a distinctive species of dolphin - and neither mix with their offshore cousins who live in deep water and this looks like being the case in northern Australia.
Under American legislation however, their false killer whales are labelled as Endangered, whereas in Australia the local populations are listed as Cetaceans, with no Australian Conservation Status.
"We would like to update the conservation status of false killer whales," said lead researcher, marine biologist Dr Carol Palmer.
"The Australian false killer whales could be genetically unique and also endangered. We need more data to know for sure," Dr Palmer said.
In Hawaii there are two populations of the coastal false killer whales, one of around 250 individuals and another of about 500.
It is unknown how many are in the Australian populations.
"I think in Australia though the populations are naturally small, but we need to get the funding to put together an accurate population estimate," Dr Palmer said.
The Australian false killer whales seem travel along the coast, with one tagged individual travelling 7500 kilometres over 105 days, about the same speed as an Olympic long-distance swimmer, she said.
"The tracking and genetic testing did show that the false killer whales covered a huge range across Northern Australia."
First Nations rangers from across the Top End (and the Kimberley), including rangers who were part of the Marine Megafauna workshop including false killer whale research, met at the CDU's Waterfront campus in mid-February to discuss the findings of this latest study and ongoing marine megafauna work to be carry out in the unique sea country of the NT.
Read the research here.
