Shark encounters and sightings along California's coast are at their highest level in decades, scientists say, warning that warmer waters mean beachgoers will have to be on the lookout for the predators all summer.
The latest near-deadly encounter came in late May when a 52-year-old woman was mauled by a shark near Los Angeles, prompting beach closures for several days.
Chris Lowe, director of California State University's Long Beach Shark Lab, said there have been more sightings of great white sharks this year than in the previous 30, and that even hammerheads have been spotted along the coast.
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He said the El Nino weather pattern of the last two years has led to unusually warm waters in the eastern Pacific, meaning the sharks and other species are not migrating -- and are moving closer to shore.
"They are going to hang out near our beaches all summer," Lowe told AFP.
The high water temperatures are having an effect on other marine life as well, with whales, dolphins, seals and sea lions increasingly spotted off the coast.
Other non-indigenous marine life has also been reported, including manta rays and hundreds of thousands of red tuna crabs that washed ashore in southern California in May.
Even a striped dolphin, normally found in tropical waters, was spotted in northern California this year.
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More worrisome are highly venomous yellow-bellied sea snakes, normally found in the tropical waters of the Pacific or Indian oceans, several of which have washed ashore in southern California.
"There have been whales staying in the area all year round rather than the usual three months," said Elliott Hazen, of the National Oceanic and Atmospheric Administration, noting they normally migrate up to Alaska to feed and down to the warmer water off Mexico to breed.
Hazen said a spike in the anchovy population was one reason three to four times more humpback whales had stayed in the Monterey Bay area in the last two years.
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