"I was also thinking they eat seals, and I'm in a black wetsuit," Johnson told 1 News.
Then she said she decided to return to the water to complete a training swim, and the whales -- an adult, a juvenile and a calf -- returned to swim with her.
Johnson said her fear quickly disappeared after she gazed into the largest orca’s huge eyes.
"It was so different to anything that’s happened to me before, and I thought, no, this is a life-changing experience,” Johnson said.
She told 1 News, "They were as interested and curious about me as I was about them."
An orca expert told the news station that killer whales are “just big dolphins with a fancy paint job,” and in fact are the largest members of the dolphin family.
Killer whales are carnivores and eat sea lions, seals and sometime other whales, but according to National Geographic, they are not known to attack humans, and at least one whale website said there's never been a report of an orca in the wild eating a human.