Drone footage captured killer whales taking turns eating a shark in Northern California. (Slater Moore Photography)

Shortly after Monterey Bay Whale Watch took about a dozen hopeful whale-watchers out to sea last Tuesday, the group received a call from a fishing boat.

“Hey, is anyone whale watching? I’ve got some killer whales up here,” Katlyn Taylor, a marine biologist with the California company, recalled the fisherman telling them.

They set out for the coordinates, about 40 minutes away, unsure of what they would be able to see by the time they got there. Nevertheless, the passengers on board the SeaWolf II were atwitter with excitement.

“It was a little overcast, but [the water was] flat calm,” said Slater Moore, a photographer who works with the company. “It couldn't have been any better to see killer whales.”

And see them they did.

When the SeaWolf II arrived, more than a half-dozen offshore killer whales began swimming near it. The group could see a similarly sized pod of whales nearby as well.

Quickly, Moore sent up his drone and began filming.

Though he has been photographing excursions like these for about five years, the thrill of a whale sighting still gets him.

“I was actually about to bring my drone in when we saw a bubble blast, a bunch of bubbles coming up to the surface,” Moore said. “The next thing you know a killer whale comes up with a shark in its mouth.”

Moore said he had to fight his own excitement to keep the drone flying steadily as he observed what it was recording: an adult offshore killer whale with a shark — still alive and wriggling — in its mouth.

Next to the adult was a whale calf, keeping close to what Taylor said was likely its mother. They estimated the adult whales were about 20 feet long or less.

Soon, other whales joined them, and they appeared to pass the shark to one another.

“They kind of take turns,” Moore said. “One grabs the shark. The other ones peel off and circle around. . . . We were kind of just super excited, everybody standing up.”

That night, both Monterey Bay Whale Watch and Moore uploaded the video to social media, where it has since been watched hundreds of thousands of times.

“It’s pretty phenomenal footage,” said Deborah Giles, research director for the Washington state-based Center for Whale Research.

Of the three well-known ecotypes of killer whales that appear on the western coast of the United States — offshore, fish-eating and mammal-eating — the offshore killer whale is the least commonly seen, Giles said.

That's because they tend to hunt their prey farther offshore, hence their name.

In fact, for a long time, it was only through secondary observations that scientists knew offshore killer whales ate sharks.

“That came about by animals washing ashore and their teeth were fairly ground down” from the tough skin that sharks had, Giles said.

She said she couldn't recall seeing anyone document offshore killer whales feeding on a shark from above.

“I don't think anybody's gotten any drone footage of it,” she said, adding that the use of drones to capture aerial video has also been instrumental in research lately. “If you’re in a boat, you’re only seeing a part of the whales, so I think the drone footage is really great for that behavior.”

Taylor, the marine biologist who was on board the boat, said the company has had encounters with offshore killer whales before but no footage of them with their prey.

“Another reason I think we miss out on the documentation of what those whales are eating is because they’re eating underwater,” Taylor said. “I think [the whales in the video] brought the shark up to the surface because the calves can’t hold their breath that long.”

In the beginning of the video, Giles points out that the whale is carrying the shark upside down in its mouth.

That is intentional and intended to suffocate the shark, she said.

“They go into something called catatonic immobility,” Giles said of sharks. “If they are turned upside down, they just stop moving. It's a chemical reaction that happens . . . and that's what the whale's doing. It's pretty smart.”

Giles said it is likely that the adult offshore killer whale is exhibiting teaching behavior as it swims with the shark in its mouth, then passes it on to another whale with the calves nearby.

Passing the food back and forth is also typical behavior among killer whales.

“With regard to prey-sharing, it’s very, very well documented in even fish-eating killer whales,” Giles said. “They actually go out of their way to share food.”

But to Giles, the most beautiful thing about the video is not the rarely documented shark feeding but something she has long loved observing across all ecotypes of killer whales.

“For me, killer whales are so interesting because they’re very socially bonded and you can see that in this video,” Giles said. “Even though the ocean is massive and they could go really far away from each other, they don’t. . . . It's one of the beautiful things about the drone footage that’s coming out. We’re learning more and more and, as different technologies come out, we’ll learn more about offshores.”

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