Slideshow temporarily missing, see transient orca photos here.

POULSBO — Flipping and swimming about, a pod of at least five transient orcas, known as Bigg’s whales, were spotted frolicking in Liberty Bay Thursday afternoon.

Identified by the National Oceanic and Atmospheric Administration’s Northwest Fisheries Science Center, the orcas are a grandmother, T30; her adult son, T30A, age 27; T30’s daughter T30B, age 20, with her new calf T30B1, born last year; and T30’s juvenile offspring T30C, born in 2005. The pod was also spotted with a larger group of about 17 orcas over the last few days around Puget Sound, including off Shilshole Bay in Ballard and Point No Point in Hansville.

Washington state ferry passengers reported seeing the whales since about 8 a.m. in Port Orchard Bay, between Bremerton and Bainbridge, posting a photo to the Orca Network’s Facebook page.

Howard Garrett, executive director of the Orca Network, said Bigg’s whales are unpredictable in their travel patterns, but that group is known to Puget Sound waters.

“To go that far into Liberty Bay is unusual,” Garrett said. Bigg’s whales are mammal eaters, and the T30 group was looking for seals, sea lions and porpoise.

“They are picking off seals mainly, that’s their sausage,” Garrett said. “They’re very stealthy, they tend to zig-zag around when on the hunt.” Garrett said Bigg’s whales don’t use echolocation to find their prey, and it’s still a mystery to scientists how the whales are able to sneak up on seals, which hear very well.

“They’re searching into inlets and shallow waters for seals. They know where to go,” he said. “It’s very hard to track or hear or see until had they’ve had their feast.”

The whales were spotted around Liberty Bay because they were celebrating, he said. Now, they’ll go back into stealth mode.

Onlookers reported seeing the whales consume a full-grown seal near the Poulsbo Yacht Club.

Transient orcas are having a tougher time than resident orcas, which primarily eat chinook salmon but are “searching high and low” for the endangered fish, Garrett said. He said there is a lively scientific debate right now as to whether Bigg’s should be classified as a different species because they’re so different from residents.

The transients are named after Mike Bigg, a pioneer in orca research, Garrett said. Because of the Marine Mammal Protection Act of 1972, Bigg’s whales are flourishing.

Reader Lowell Sannes contributed a photo slideshow of the orcas’ visit to Liberty Bay.

Wildlife officials remind people to say at least 200 yards away from all orcas. In 2011, the NOAA Fisheries Service adopted new regulations under the Marine Mammal Protection Act and Endangered Species Act to protect all killer whales in inland waters of Washington: don’t position your vessel within 400 yards in the path of oncoming whales, and stay 200 yards (the distance of two football fields) away at all times. Info: www.bewhalewise.org/new-regulations.