Killer taste: Bite mark analysis shows killer whales target sharks for their liver

Killer whales in Australia deliberately hunt sharks for their liver, DNA evidence has shown. 

A pod of orcas in the process of killing a great white shark near the Neptune Islands. (ABC News)

DNA analysis from a shark carcass washed up in Portland, Victoria has shown killer whales (Orcinus orca) target sharks specifically for their nutrient rich liver. 

The 4.7 metre white shark (Carcharodon carcharias) washed up missing its midsection on a beach in South Eastern Australia, where scientists from Flinders University were able to analyse the distinctive bite wounds. 

In a new study published in the journal Ecology and Evolution, researchers from the university used wildlife forensic techniques to confirm killer whales were responsible for excising and consuming the liver from the white shark.

The body of the white shark washed up in Portland, Victoria. Credit: Flinders University/Ben Johnson

“The liver, digestive and reproductive organs were missing, and there were four distinctive bite wounds, one of which was characteristic of liver extraction by killer whale,” said lead author Isabella Reeves.

“Swabs were taken from bite wounds on the white shark and sequenced for remnant genetic material from the shark’s predator. We were able to confirm the presence of killer whale DNA in the primary bite area.”

“These findings provide compelling evidence of killer whale predation on white sharks in Australian waters, with a strong indication of selective liver consumption. This suggests that such predation events may be more widespread and prevalent across the globe than previously believed,” said Reeves. 

Infographic of Reeves et al. 2025 study based on using DNA to identify that killer whales killed white shark carcass for liver. Picture: Emma Luck

Globally, killer whales have been observed preying on various shark species including white sharks – as previously documented in California and South Africa.

In Australia, killer whales have occasionally been recorded preying on various shark species, including blue shark (Prionace glauca), porbeagle (Lamna nasus), shortfin mako (Isurus oxyrinchus), ground sharks (most likely school shark, Galeorhinus galeus), and tiger shark (Galeocerdo cuvier). 

Although, despite numerous reports of such behaviour in California and by the notorious duo ‘Port’ and ‘Starboard’ in South Africa, white shark liver consumption had yet to be observed in Australia.