Scientists Explain Video of Orca Punting a Seal 80 Feet in Air

orca-seal
Off British Columbia, an orca flips a seal high into the air with its tail fin, in a video that has gone viral. Roll.Focus Productions/YouTube

You've probably never seen a seal fly before. That's about to change.

Below you can see a video of a seal being launched very high into the air by a killer whale, which hits it with its tail fin and sends it flying.

The clip, captured by a whale-watching company called Eagle Wing Tours and its video production company, Roll Focus Productions, off the coast of Victoria, British Columbia, has already been viewed more than a million times on YouTube. We thought we'd find out what exactly is going on: Is this a common occurrence when orcas hunt seals, or was this more of a fluke?

Rüdiger Riesch, a scientist at the University of London, says that killer whales often strike seals with their tails.

"A lot of marine mammals, like seals and sea lions, have very sharp claws and teeth, so killer whales are at risk of suffering a severe injury when hunting these prey," Riesch explains. "Therefore, the safest course of action is for the killer whales to debilitate their prey before getting anywhere near them. To do this they use a combination of rams, often head-on, and slapping the prey with their flukes, or tail fins. This can go on for 30 minutes or more, until the seal or sea lion is too injured to fight back or potentially already dead."

Usually the tail-strikes don't launch the seals into the air, though Riesch has seen it happen a handful of times off Vancouver Island while he was there doing research on "transient" killer whales, he says. (Transient killer whales are group of the animals that feed on marine mammals like seals, whereas "resident" orcas feed on fish.) But this particularly video still surprised him: "I have not yet seen a seal getting flipped quite that high up into the air."

The killer whales also may kick up the seals to loosen the animals' skin, which they don't eat, says Ingrid Visser of the Orca Research Trust in New Zealand. She adds that she has seen orcas launch seals into the air many times in Argentina.

Inuit living in Nunavut, in northern Canada, have also witnessed this attacking technique, says Kristin Westdal of the Pew Charitable Trusts' Oceans North Canada. Besides helping to disable the prey, the orcas might fling them up into the air just "for fun," a cetacean version of "playing with its food," Westdal says.

This "flipping ability" is a type of learned hunting technique that is passed on through family groups, says Steve Ferguson, a researcher with the University of Manitoba. "Some use it and some don't…. Sometimes this behavior has been attributed to mothers teaching their young how to hunt, [to make] the prey easier targets."

Scientists Explain Video of Orca Punting a Seal 80 Feet in Air | Tech & Science