Rare orca sightings thrill scientists, whale-watchers

Orcas spotted off the coast of San Diego in recent weeks are mysterious visitors that typically wander the open ocean, researchers said.

A group of five orcas have been seen several times since late December, traveling between Los Angeles and San Diego and exciting whale-watchers and scientists alike. The sightings included one in Carlsbad on Dec. 30 and one near the Mexico border on Jan. 8.

“It’s pretty rare to see them off San Diego,” said Alisa Schulman-Janiger, a researcher with the California Killer Whale Project.  “We don’t know why we’re seeing them this time of year, but we have been seeing them a little more often.”

The family of five are Eastern Tropical Pacific orcas, members of a wide-ranging but little-known population, researchers said. Although other populations of killer whales have clearly defined territories and diets, these travel from San Diego south to Central America, and have mostly eluded observation. Scientists have been eager to get a glimpse of the enigmatic orcas.

“Every single encounter is like a treasure trove,” Schulman-Janiger said. “Getting those pictures and information can fill in a lot of holes.”

The family group, including a calf and a male with a wavy tail, first appeared near La Jolla on Dec. 27, and then again off Oceanside and Carlsbad on Dec. 30, Schulman-Janiger said. Oceanside Harbor Police spotted them there, and Fox 5 News posted a short videotape showing one of the black and white animals swimming.

The orca family showed up between Los Angeles and Laguna Beach on Jan. 7, and again at the Mexican border Jan. 8.

Troy Sears, captain of the whale-watching yacht “America,” said he saw two of the orcas swimming near the border that day.

“They were just roaming,” he said. “When we were with them they were southbound. On the radio we heard different directions. Different people saw them at different times of day.”

Scientists don’t know exactly how many Eastern Tropical Pacific killer whales there are in the world, but have cataloged 195 of them, said Ann Bowles, a senior research scientist with Hubbs Seaworld Research Institute. 

One of the big questions is what they eat, researchers said. Unlike other groups of orcas that specialize in a single prey such as seals or salmon, these wanderers probably dine from a diverse menu.

Film footage from the 1980s showed several of them attacking a blue whale, she said, so scientists think that marine mammals form at least part of their diet. When the group appeared in Los Angeles on Jan. 7, Schulman-Janiger said she saw them scatter a pod of dolphins, supporting the conclusion that they prey on other mammals.

“When I saw them, we did see a big group of common dolphins suddenly took off at very high speed,” she said. “Most likely from that flee response, these (orcas) are dolphin or mammal eaters.”

Eastern Tropical Pacific orcas spend much of their time on the high seas, so they may also eat sharks and rays, Bowles said.

“These guys are successfully making a living swimming out in the Central Pacific Ocean,” she said.

Scientists aren’t sure what ocean conditions prompted the family’s appearance off the coast of Southern California this year, Bowles said. But the visit from the wandering whales represents a chance to learn more about their population, she said.

“They’re so widely scattered,” Bowles said. “You get on them by luck. So when they do come in, everybody gets really excited and tries to find out as much as they can.”

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