Shortly after noon a 6-8 foot hammerhead approached a kayak fisherman 1 1/2 to 2 miles offshore. The fisherman paddled toward shore with the shark following.
About 250 yards from the beach, the fisherman flagged down a lifeguard rescue boat. The lifeguards saw the shark head toward a swimmer, then turn away and swim toward deep water.
San Diego Lifeguards extended the shark advisory already in effect through the end of the day Sunday, but did not close the beach again.
On Saturday, a hammerhead circled a group of kayakers, prompting lifeguards to close the beach for the rest of the day.
Hammerhead sharks are rarely seen near the shore, Lt. Andy Lerum of San Diego Lifeguards said. However, warm weather and currents from the south made San Diego waters warmer than usual.
According to Lerum, water temperatures were about 74 degrees at La Jolla, which made the beach an ideal condition for the shark.
Experts at the Birch Aquarium concurred with the beach closures because they were concerned by the shark’s behavior, he said.
City News Service contributed to this article.