It’s a Whale Eat Whale World
The killer whale, shown in this photograph, has a glossy black back, a white underside, and a white patch near each eye. Its powerful, swift body helps make it an effective predator.
© Brandon Cole, Alamy Images
Australian scientists reported in January 2022 their observations on three instances where a pod of orcas viciously attacked, killed, and consumed a blue whale—the largest of all animals. The scientists described the attacks as “the biggest predation event on Earth,” the likes of which may not have occurred since the age of the dinosaurs. The titanic battles also settled a long-standing debate among scientists on whether gigantic blue whales could be vulnerable to the ocean’s top predators.
The blue whale is the largest animal that has ever lived. An adult reaches up to 100 feet (30 meters) long and can weigh over 150 tons (135 metric tons)—larger than even the largest dinosaur. Orcas, also known as killer whales, are apex predators at the top of the food chain in every ocean of the world. Adult males typically measure from 19 to 27 feet (6 to 8 meters) long and weigh 4 to 10 tons (3.6 to 9 metric tons). Females are usually somewhat smaller. They often travel in groups, called pods, up to dozens of animals, usually led by an adult female. Orcas feed on a wide variety of ocean animals, but some pods are known to specialize in hunting large whales.
The scientists reported their observation of three separate orca attacks on blue whales that took place from 2019 through 2021 off Bremer Bay in Western Australia. In two of the attacks, a large pod of orcas was seen to attack, kill, and consume blue whale calves up to about 40 feet (12 meters) in length. A third attack was observed on a fully grown adult blue whale about 72 feet (22 meters) long. Up to 12 orcas cooperated in a gruesome hour-long attack led by 8 adult females as dozens of juvenile orcas circled about. The orcas attacked as a pack, biting and ripping flesh from the enormous whale as it desperately tried to flee. The scientists watched as one orca forced its way into the dying giant’s mouth to tear away and eat its massive tongue. Once the blue whale expired, about 50 orcas surrounded the great beast to feast on the carcass.
Orcas have been observed hunting every kind of large whale in coordinated packs, much like wolves. However, orcas are almost always observed preying on calves, rather than fully grown adults. More than three times their body size, an adult blue whale poses a formidable and dangerous challenge to any orca that dares attack. Scientists also believed that taking such large prey must have relied on attacks led by the larger males in the pod.
Now, scientists have observed that orca attacks against adult blue whales are successful and are often led by females. They believe that such predation by orcas may have been more common in the past before the blue whale population was decimated by whaling in the past 150 years. Such attacks may be led by mature females who have learned coordinated pack techniques to take down large prey.
