Orcas hunt great white sharks in Australian waters and eat their livers, 50cm bite mark confirms
Orcas hunt great white sharks in Australian waters and eat their livers, 50cm bite mark confirms
Share:
Behaviour of ‘remarkable predators’ also seen off coast of South Africa could affect ecosystem, researchers say. Orcas have a taste for shark liver and prey on great white sharks in Australian waters, researchers have confirmed by using DNA analysis.
![[Coordinated effort needed to stop whales getting tangled in ropes and nets, scientists say – video]](https://i.guim.co.uk/img/media/49fbc6489d17a30b5c8d47247a14427fb80b10f6/0_0_1920_1080/1920.jpg?width=465&dpr=1&s=none&crop=none)
In October 2023, the maimed carcass of a 4.7m great white shark washed ashore near Portland, in southwest Victoria, missing its liver, digestive and reproductive organs. Two days earlier, citizen scientists witnessed several killer whales, including locally catalogued animals known as Bent Tip and Ripple, catch large prey in the area.
Suspecting a killer whale was the behind the shark’s death, researchers swabbed and analysed DNA samples taken from the distinctive bite wounds. The results, published this week in Ecology and Evolution, confirmed the presence of killer whale DNA in the area around the largest bite, a wound measuring 50cm in diameter near the shark’s pectoral fin. Tests also found the presence of genetic material from scavenging broadnose sevengill sharks in three smaller bite wounds.
Sign up for Guardian Australia’s breaking news email. This was the first confirmed evidence – using DNA and citizen science data – of orca predation on great white sharks – also known as white sharks – in Australia, and their likely selective eating of shark liver in Australian waters.
Isabella Reeves, a Flinders University researcher and the lead author of the findings, said “killer whales and white sharks are both top predators”. The carcass found in Victoria had “four distinctive bite wounds”, she said – one showed killer whales had deliberately torn out its liver.
