Stella Phol was on the water when this happened - her friend, who's a marine biologist, recorded video of a 10-foot great white swimming just 10 feet away from her.
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She says she remained calm.
"It wasn't interested in us in any threatening way. It wasn't following me," she said.
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Biologists say shark season runs from May through October, when sharks give birth and shark sightings increase.
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