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.
Biologists say shark season runs from May through October, when sharks give birth and shark sightings increase.
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