Some people on whale watching cruises have been treated to dramatic views recently of killer whales, also known as orcas, hunting off the San Diego coastline. At least two pods of the mammals have been roaming up and down the Southern California coast.
And it’s no surprise to see these creatures so close to the coast.
“Most killer whales tend to be close to the coast because that’s where most of the food is. The ocean is most productive along coastlines on the continental shelf. Actually if you’re looking for killer whales in the ocean, along the coast is where you want to be,” said marine ecologist Bob Pitman.
Pitman spent most of his career working for NOAA Fisheries in La Jolla. He’s now with the Marine Mammal Institute, at Oregon State University.
He and other experts said the killer whales that Californians have lately seen reside in the Eastern Tropical Pacific, off Mexico and Central America. In fact these orcas are called ETPs.
They are mammal specialists, which means they hunt dolphins, sea lions and some whales. Pitman said these days there’s more prey for orcas off the California coast.
“We protect marine mammals now. After a couple centuries of whaling and indiscriminately killing marine mammals,” he said, adding that the numbers of dolphins and whales are increasing.
“When those animals were taken out of the ecosystem their predators undoubtedly took a hit too. And (now) their predators are probably increasing now alongside their numbers.”
“Killer whale” became a common name for orcas, a member of the dolphin family, because they were known to attack and devour whales.
Earlier this month a fin whale was run aground and died on Pacific Beach. The evidence made it pretty clear what drove the whale onto the beach: NOAA biologists saw killer whale tooth marks on the body.
Marine biologist Alisa Schulman-Janiger said orcas are called the wolves of the sea because of the way they hunt whales.
“Some will try to ram the whale. Some will try to grab the flippers and pull them down. Some will try to get on the head of the whale, and use their body weight to push the head underwater so it can’t breathe,” said Schulman-Janiger, with the California Killer Whale Project.
Both she and Pitman belong to the academic world but they have many connections with companies that offer whale watching rides to tourists. Pitman said a recent paper he and Schulman-Janiger collaborated on owed a lot to tourists, citizen scientists and their smartphone cameras.
“The majority of data in that paper was posted on social media. You know, there are a lot more whale watchers and whale watching public out there than there are researchers and so this is a new vein for researchers to mine,” Pitman said.
Pitman said another academic paper, now under review, would separate killer whales into various species, depending on their diet. He added that while the mammal-eating killer whales are doing very well, the ones that specialize in eating fish are eating the same kind of fish that humans do. And they are doing less well.
