2 swimmers in San Francisco bit by sea lions 24 hours apart

One sea lion chomped down on a man's upper arm.

— -- Two swimmers were bit by sea lions in San Francisco Bay this week, prompting officials to close a popular water park on Friday.

The sea lion attacks occurred less than 24 hours apart near Aquatic Park Cove in San Francisco, officials said.

The Golden Gate National Recreation Area officials issued a stern warning to swimmers on Twitter: "At this time we recommend AVOID THE AREA SWIM AT YOUR OWN RISK AT AQUATIC PARK."

A follow-up tweet declared that the park was officially shut down to swimmers until public safety agencies could determine a “safety plan regarding sea lion(s).”

Swimmer Christian Einfeldt spoke to ABC News affiliate KGO just before he went into surgery at Zuckerberg San Francisco General Hospital. He explained how he survived his encounter with a male sea lion.

Einfeldt said he was a quarter mile from shore when a male sea lion started to track him in the water.

He admitted "there was nothing I could do" and the marine animal chomped on his upper right arm.

After the sea lion released him, Einfeldt said he felt strangely at ease.

"I was relatively calm because I wasn't dead," he said.

Einfeldt, who was bleeding, managed to be lifted to safety when a sailboat's captain saw him and plucked him out from the water.

Despite being bitten by the sea lion, Einfeld said he has no plans to stop swimming.

"I'm going to be swimming in waist-deep water," he said. "This is their kingdom, I don't want to roll the dice a second time."