SAN FRANCISCO (KGO) -- Cellphone video of a great white shark eating a sea lion has been getting a lot of attention the last few days. It was shot by a tourist on Alcatraz Island. Biologists say they have tracked sharks in San Francisco Bay before, but never one that's made it all the way to The Rock. This may be the first time a shark has been spotted so far into the bay.
"There's never been an encounter with a human in the bay, but we have seen them," said David McGuire with Shark Stewards. "It's shocking, a little bit, to see one right next to the Alcatraz dock, right in front of a boatload of tourists."
The video quickly made the rounds at the Dolphin Swimming Club where quite a few members are training for a race this weekend. They'll be jumping in at about the spot where the video was shot.
"It was scary to see a big pool of blood in the water, definitely scary," said San Francisco resident Ryan Dalton. "It's something that you don't want to think about while you're in the water."
About 80 swimmers are expected to compete in the race that stretches from Alcatraz Island to the swim club at San Francisco's Aquatic Park.
Longtime swimmer James Vanya says sharks have probably been feeding in the bay for a while.
"Everybody have a camera now," he said. "He cannot escape anymore .everybody can see you."
October has been dubbed "Sharktober" by surfers because this is when the predators are most active in this area. So people should be careful in and around the bay.
"Lifeguards will post if there's a sign," said McGuire. "And look at nature. Look at the circling of birds, if there's a lot of activity under the water, if seals are swimming away quickly you should probably get out of the water because there's may be a shark preying."
The waters outside the Golden Gate Bridge until the Farallones are among the three most active shark feeding areas in the world.
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