Orcas – also known as killer whales – are known for their highly specialised hunting techniques, taking down large prey, including gray whales, sea lions, dolphins, and even great white sharks. These apex predators have just added another name to their hit list; for the first time orcas have been recorded hunting the planet’s biggest animal – blue whales.
According to a paper found in the Marine Mammal Science journal, a female-led pod of orcas was recorded killing and eating blue whales on three separate occasions off the Australian coast since 2019.
There had been reports over the years of orcas chasing blue whales, but attacks were largely unheard of, and authentic reports even less. This study documents the three killings, including details about how orcas will swim inside the mouth of a blue whale, to eat its tongue.
Two blue whales were killed and eaten within 16 days of each other in 2019, and the third in 2021.
The attacks occurred off Bremer Bay in Australia, observed from commercial whale-watching vessels, according to The Guardian.
The first attack was against an adult blue whale, approximately between 18 and 22 metres long. At least 12 orcas orchestrated the attack, and it was led by females.
Once researchers arrived at the site, the adult blue whale had most of its dorsal fin eaten, and it was missing large chunks of skin and blubber. The attack continued for an hour, in which the female whales continuously pushed the blue whale underwater until it died. Before that, one whale swam into its mouth and ate its tongue.
Over the course of the day, the carcass was devoured by more orcas and even other animals such as albatrosses and storm petrels.
The next attack was on a blue whale calf, only between 10 and 12 metres long. This time a larger pod of orcas attacked, of which the majority were females. It was once again observed that an adult female orca stuck her head inside the blue whale’s mouth to eat the tongue.
The carcass was mostly eaten by orcas, in a less frenzied manner than the first.
The final attack was on a 12 to 14 metres long yearling, which was chased for over an hour. The orcas used the same strategy to kill and devour the carcass.
These documented attacks hold great scientific significance, as it contributes to understanding how orcas shape marine communities, and how they may or may not affect blue whale populations.
Picture: Getaway Gallery
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