A hammerhead shark in the Sea of Cortez, Mexico. His cousin is apparently in La Jolla today.

San Diego Lifeguards have closed La Jolla-area beaches after several kayakers recorded an encounter with a hammerhead shark. The encounter was caught on video.

Lifeguards say the footage shows one 8- to 10-foot hammerhead circling around the kayaks and exhibiting what they are calling “aggressive behavior.”  After the kayakers brought their video back to lifeguards, they immediately took action and requested that everyone leave the water. They cleared the waters between La Jolla Cove and Scripps Pier, and the beach will be closed for at least the next 24 hours.

Crews in boats and a helicopter have begun searching the ocean for the shark. Officials say if they find it, they will track it and make sure it leaves the area before the waters are reopened.

It’s important to note that hammerhead sharks are not normally aggressive towards humans – we’re simply not on their menu. As of 2011, the International Shark Attack File lists 34 bites attributable to hammerhead sharks, with 17 of them unprovoked and none fatal.

Hammerheads range from 3.0 to 19.7 feet in length and weigh from 6.6 to 1,278.7 pounds. They are usually light gray and have a greenish tint to them, with white bellies that allow them to blend into the ocean when viewed from the bottom. Their heads have lateral projections which give them a hammer-like shape. Hammerheads have disproportionately small mouths and seem to do a lot of bottom-hunting. They are also known to form schools during the day, sometimes in groups of over 100. In the evening, like other sharks, they become solitary hunters.

This story will be updated as soon as someone sends us something that we can share. If that’s you, please click here.