"A vessel named the Grey Goose was calling," SFPD Marine Unit Officer Matthew Reiter told reporters. "They had seen a swimmer in distress, and they reported that he had been bitten by a sea lion and he was bleeding very badly."
Long-time bay swimmers say a serious sea lion attack is almost unheard of.
"People have been nibbled over the years here and there. No one's ever been seriously hurt," said George Howell, who's been a member of the Dolphin Club since 1982.
Police say the 56-year-old man was bitten while swimming near the mouth of the Aquatic Park Cove. He flagged down the Grey Goose, a rented sailboat on its way back to Sausalito. The captain brought him aboard and followed instructions from authorities over the radio to bring him to shore.
"It looked like a bite wound on his right upper arm," Reiter said. "It was uncontrolled bleeding when he came onto our dock."
Reiter said police put on a tourniquet to stop the bleeding, then added second tourniquet and pressure dressings in the ambulance. The swimmer was taken to San Francisco General Hospital, where officials later upgraded him to good condition.
"If they really sunk their teeth in, they could pretty much leave with your feet," Howell said, adding that sea lions tend to reserve that level of aggression for fish. "I've never heard of anybody going to the hospital or getting stitches."
Howell points out this is mating season -- a time of year when male sea lions can get aggressive. He says he's always been taught the best course of action is to swim away gently and avoid blowing bubbles, since male sea lions can interpret bubbles as a sign of aggression.
Police say the swimmer was startled by the large mammal.
"The sea lion was coming at him and he said he felt threatened, and that's why he started splashing water and trying to yell at it to get away, but it bit him," Reiter said.
Reiter recommends swimmers stay in pairs whenever possible.
"I mean, the boat saved his life. If the boat hadn't been there, who knows what would've happened," he said.