SAN FRANCISCO – A few penguins swimming leisurely at the San Francisco Zoo is nothing new. But dozens of them doing laps in unison for hours has zookeepers perplexed.

“We’ve lost complete control,” said Jane Tollini, the zoos penguin keeper. “It’s a free-for-all in here. After 18 years of doing this job, these birds are making mincemeat of me.”

It all started in November when six newcomer Magellannic penguins, formerly of Sea World in Aurora, Ohio, were brought in.

Since then the penguin pool at the San Francisco Zoo has been a daily frenzy of circle swimming by all of the 52 birds at once.

The penguins start swimming in circles early in the day and rarely stop until they stagger out of the pool at dusk.

The six penguins from Ohio started it all, Tollini said, apparently convincing the others to join them for the watery daily circuit.

“I can’t figure out how the Aurora penguins communicated and changed the minds of the other 46,” Tollini said.

Some penguin experts point to the highly social animals as being open to new ideas fostered by newcomers in to the zoo’s so-called Penguin Island.

“Penguins are extraordinarily social birds,” said Christina Slager, associate curator at Monterey Bay Aquarium. She has studied Magellanics in the wild in Patagonia and Chile.

“And they’re very, very inquisitive. If you combine those facts and put in a new stimulus, like the six new penguins, they have to check it out.”

Aquatic biologist Pam Schaller of the Steinhart Aquarium in San Francisco described it in more matter-of-fact terms.

“Genetically, they’re designed to swim,” Schaller said. “I’d be more amazed if the six had learned to do something not in penguin nature and showed the other 46 how to do it – like if the birds were trained to jump through a hoop.”