Orcas Slap, Kill, But Don't Eat Their Prey

It’s impossible to tell why the whales didn’t eat their prey, one expert says, but here are a few suggestions.

Rare video of orcas filmed in Mexico shows them toying with a stingray that eventually died, but was not eaten.

Orcas Slap, Kill, But Don't Eat Their Prey

It’s impossible to tell why the whales didn’t eat their prey, one expert says, but here are a few suggestions.

Rare video of orcas filmed in Mexico shows them toying with a stingray that eventually died, but was not eaten.

When Jorge Cervera Hauser went diving with friends in the Sea of Cortez in Baja, California, he was on a mission: to find orcas. Getting in the water with orcas is incredibly rare, Hauser says, and witnessing what they were about to witness, even rarer.

“I’ve been obsessed with orcas for more than seven years now,” says Hauser, CEO of the travel company Pelagic Fleet, “and I always seem to miss them.”

About an hour into the swim, the team spotted a pod of black-and-white whales. (Related: "Exclusive: Mysterious Orcas Filmed Underwater for the First Time")

“In total, there were around six orcas spread out in groups of two or three. Every time we would jump into the water they would only do a flyby, quickly checking us out,” Hauser recalls. “But around our tenth jump, something changed.”

The orcas noticed a stingray that had come to the surface, possibly to give birth, Hauser says. Instead of zooming by the divers, the orcas began playing with the stingray: circling it, swatting it, and grabbing it to pull it further into the water. (Related: "First Case of Foster Infanticide Observed")

Hauser says the ray was immediately stunned by the first slap, and was too weak and disoriented to get away from the whales. This behavior went on for about an hour and a half, until the whales killed the ray.

The divers suspected that after smacking around the ray, the whales would eat their prey. But instead, the orcas let the dead animal sink to the bottom of the ocean.

I have been in the water photographing great white sharks, saltwater crocs, and even green anacondas,” Hauser recalls. “The interaction I had and the behaviour I was able to witness was without a doubt the most incredible underwater experience of my life.”

Foul Play

Stingrays are common in the Gulf of California, and they’re known as a diet staple for some orca populations. The whales are known to play with their food before eating it.

“In this particular case, they were only messing around,” Hauser says.

Experts say that behavior is not uncommon. “Killer whales, and many predators, sometimes kill things that they don't eat; maybe for play, maybe just to keep their skill level tuned up,” Robert Pitman of NOAA Fisheries’ Antarctic Ecosystem Research Division writes in an email. “I have seen killer whales in Antarctica chase a penguin for half an hour, kill it, and leave it floating on the surface. At other times, they eat the penguins.”

But stingrays can be dangerous for orcas, says David Bain, vice president of the Seattle-based Orca Conservancy. Their spines, or barbs, can easily injure a young whale that doesn’t have experience taking a ray down. (Watch: "Killer Whales 'Gang Up' to Capture Seal")

Hauser says that batting the ray around, the orcas looked to him as if they were showing off in front of the divers.

“At first they were paying little attention to us and would only come to quickly check us out and leave, but when they found the ray, the game changed,” Hauser says by email. “It was like they were trying to show us what they were doing and switching between interacting with the ray and with us. It was over an hour of, ‘Mom! Look!’ moments.”

Though it’s possible the whales were showing off, Bain says it’s more likely the whales were making a threat display in front of the divers. They may have also been toying with the ray for practice, or they may not have been comfortable eating in front of humans.

Or, there may have been a miscommunication within the pod, Bain says. The younger whales might have killed the ray incorrectly thinking that an older one would eat it.

“It’s impossible to tell why the whales didn’t eat their prey,” Bain says. “Sometimes the kids will get an idea of what they want to do, but the parents are not having it.”