VIDEO: Pod of rarely seen Risso’s dolphins making themselves at home off Orange County

DANA POINT — A pod of about 50 Risso’s dolphins have been wowing marine mammal enthusiasts in Orange County for the past several weeks.

The dolphins, among the rarest seen in this area, have been around for at least a month. They are known for hunting squid, including the larger Humboldt squid, and experts believe their presence indicates a plentiful supply in the area.

On Tuesday, Oct. 23, the pod was spotted in about 180 feet of water of San Mateo Campground off San Onofre State Beach — rare for dolphins generally found in 1,800 feet of water.

“It’s been pretty unusual,” said Capt. Steve Burkhalter, who was aboard Dana Wharf’s Ocean Adventure. “We’re seeing them a couple of times a week.”

Burkhalter and other marine mammal experts know they keep spotting the same pod because they’ve seen Tonka — a leucistic Risso’s dolphin known by the distinctive markings on his dorsal fin — in the pack. Tonka was named by Robin Lowe, an American Cetacean Society naturalist, who first spotted him on Sept. 17. Since then, she’s seen the same pod multiple times.

“Each time we see the dolphin and get additional pictures it will help add to the story on how much of the body is affected by the leucism,” she said of the rare condition, a partial loss of pigmentation.

Tonka has multiple white patches on his dorsal fin and his saddle area and a darker circle around his blow hole.

All of the Risso’s dolphins have some type of variation in their coloring and their patterns come from scarring, likely caused by tentacles from the squid they pursue.

“The tentacles will come out and scar their bodies,” Lowe said. “As they heal, the scars turn white. It’s like a giant artist’s canvas and each one is unique.”

Burkhalter and other boat captains have seen the pod as far north as Newport Beach. The group can be spread out over several miles or in a tighter quarter-mile cluster as they were on Tuesday off San Clemente.

Typically, four species of dolphins – bottlenose, long- and short-beaked and Pacific white-sided – are seen throughout the year off the coast of Dana Point. Risso’s dolphins are the most infrequently seen. In March, a group of 100 Risso’s dolphin were seen off Dana Point.

Unlike the common dolphin and the bottlenose that love to bow-ride and are very active, Risso’s are mellow and just come up and breath, Burkhalter said. But on Tuesday, Burkhalter said he observed a more active behavior.

“They were doing tail slaps and some were spy-hopping,” he said.

Lowe encourages anyone who sees an oddly marked whale or dolphin to photograph it and send it to Happywhale.com.

“I was waiting for Tonka to come completely out of the water, that way we can see the whole body and learn more about his story,” she said.