First there was a thump, then a thud as the early-morning mugger took off with Cathie Dias's hat as she jogged through Beacon Hill Park in Victoria, B.C.
He didn't give a hoot that he was seen by her friends, and, as the shaken runners came around the loop for the second time, he repeated the attack, this time whacking two of them on the head.
"It was really quite scary," said Dias, who had seen the large owl swooping in front of her before it landed on her head and stole her hat on Wednesday morning.
"If that had happened to me while I was by myself, I would really have freaked out."
Dias let out a "bloodcurdling scream" as the owl pounced, but her friends thought she was complaining about the workout.
After she told them what had happened, they figured the owl attack was probably a one-off and decided to repeat the same loop, but as they approached the same area, the owl was perched on a tree, waiting.
"He was definitely lurking," Dias said.
Sure enough, the owl swooped at one of the men, who yelled and apparently unnerved the bird. It then took a dive at a third runner and whacked him on the head.
That was enough for everyone, and it was decided not to run another loop, said Dias, who is unsure what route to now take on her morning runs.
"I guess it's nesting time and the birds are being protective," said Dias, who told Victoria park officials about the incident and is hoping that a sign can be erected to warn people if there are more attacks.
"I wouldn't like to think of this happening to a child or a senior," she said.
There is no sign of the wool hat snatched by the owl, Dias said.
"It's nice to know my black and grey running hat will keep some baby owls warm this spring," she added.
The parks department has identified the bird as a barred owl.
Christina Carrieres, wildlife rehabilitator at B.C. SPCA's Wild Animal Rehabilitation Centre, said the bird is probably a male either nesting or looking for a good area for a nest.
The behaviour is the same used by many birds trying to protect their nests, Carrieres said.
Once owls lay eggs, they take about a month to hatch. If the attacks continue during that time, it might be necessary to warn people to stay away, Carrieres said.
"We can't control them, so we have to control ourselves," she said.
"Seeing the runners coming back and back and back must be really frustrating for the owl. He was just trying to get his message across."
Last November, a Seattle area park had to be temporarily closed because of attacks by barred owls.
The young owls, apparently trying to establish their territory, seemed to target people wearing headphones or with their hair in ponytails.
Experts said the birds may have been mistaking ponytails for squirrel tails.