The killer whales that swam up to former Olympian Silken Laumann's dock this weekend are a famous family of transients known for their hunting prowess, according to an orca expert.

Laumann told CBC she was in the shower Saturday when she looked out the window and saw a crowd of whale-watching boats gathered off her property on Henderson Point in the Saanich Inlet.

"I grabbed my robe and I was yelling, 'Whales!'" the champion rower remembered.

She ran down to the dock with her 19-year-old daughter, who grabbed her phone and started taking video as five killer whales swam right up to the dock and then past it.

"It was just one of those experiences. Both our adrenaline just went through the roof," said Laumann, founder of a story-sharing platform called Unsinkable.

"I've seen [the documentary] Blackfish, so there was part of me that was crouched on the dock, thinking, 'Is this a good idea?'"

We are freaking out with joy at the sight of these beautiful creatures off the end of our dock minutes ago! <a href="https://twitter.com/hashtag/exploreBC?src=hash&ref_src=twsrc%5Etfw">#exploreBC</a> <a href="https://twitter.com/hashtag/whales?src=hash&ref_src=twsrc%5Etfw">#whales</a> <a href="https://t.co/wnVwsgORCL">pic.twitter.com/wnVwsgORCL</a> —@SilkenLaumann

The orcas are known as the T65As, a family of mammal-eating transients, or Bigg's killer whales, according to Kelley Balcomb-Bartok, communications director for the Pacific Whale Watch Association.

Their matriarch is called Artemis, for the Greek goddess of the hunt, and in the video, the whales appear to be hunting.

"They're famous around here for their hunting skills," Balcomb-Bartok said. "They're some of the most powerful and incredible hunters that you'll see out here, and so it's very exciting."

'A really amazing, amazing group of animals'

Born in 1986, Artemis travels with her five offspring, including a youngster born in the spring of 2018. Four of those offspring can be seen in Laumann's video. The other one, a teenage male, sometimes likes to head off with an aunt, Balcomb-Bartok said.

The family is known to range as far north as Alaska, but they're seen so frequently in the inside waters of B.C. and Washington state that they could almost be called "resident" transients, he added.

"That particular group is a really amazing, amazing group of animals," he said.

The T65As are known for their hunting prowess. (Pacific Whale Watch Association)

Though the fish-eating southern resident killer whales have been struggling in recent years, the transients are thriving, finding ample seals, sea lions and other marine mammals in local waters. According to Balcomb-Bartok, Bigg's orcas have been seen every day in the Salish Sea for 90 straight days.

"We've had almost 100 animals born to the Bigg's population in just the past eight years," he said.

Killer whales used to be an infrequent sight from Laumann's property, but she said they've started appearing more regularly.

That may have something to do with all the seals in the neighbourhood.

"We actually had a seal born on our dock the week before. It's just been this hotbed of activity, our dock," Laumann said.

For more on the plight of the southern resident killer whales, check out Killers: J pod on the brink. You can get it now for free at CBC Podcasts.