On an Antarctica expedition, photographer and filmmaker Bertie Gregory witnessed what looked like two humpback whales saving the life of a Weddell seal from a pod of killer whales.
A lone seal was resting in the middle of a big, flat chunk of ice, per National Geographic. Generally, orcas try to knock their prey off of ice chunks by making a unique type of wave. But this time, according to Gregory, they did something unexpected.
“They swam under the chunk of ice, just like they normally do, but we could see no breaking wave, and we were like, ‘Oh, they must have messed it up.’” Gregory told National Geographic. “But instead they were making an underwater shockwave.”
The pod of orcas eventually forced the seal into the water.
“Then, all of a sudden, two humpback whales just turn up,” Gregory told National Geographic. “They do this amazing trumpeting noise (that’s) so loud, it reverberates in the hull of the boat, like an elephant trumpeting.”
Although the two humpbacks arrived too late to save the seal, the trumpeting and direct entrance into the orca pod led Gregory to believe “the pair were trying to mess up the orca’s hunt and even protect the seal,” National Geographic reported.
Why did the humpback whales intervene?
Lori Marino, president of the Whale Sanctuary Project, said it isn’t “completely surprising” that humpback whales protect other animals from orcas.
“Although this behavior is very interesting, I don’t find it completely surprising that a cetacean would intervene to help a member of another species,” Marino said, according to National Geographic.
Many humpback whales that interfere with orca attacks have scars from previous killer whale encounters. Alisa Schulman-Janiger, lead research biologist for the California Killer Whales Project, told The Tyee that some humpbacks may be reacting to previous trauma. There is evidence that traumatic memories of orca attacks motivate humpback whales to protect other cetaceans in similar situations.
Since orcas prey on young humpback whales, these interactions can also be generalized as “anti-predator behavior,” per Reader’s Digest. Whether the reason is preservation of their own species, trauma or altruism, killer whales and humpback whales have a history. In fact, over the past 60-plus years, there have been more than 115 recorded encounters between orcas and humpback whales, according to National Geographic.