Sixty feet.

That is the average distance between a shark and a swimmer, or surfer, from January through March along South Florida beaches, according to Steve Kajiura, director of the Elasmobranch Research Laboratory at Florida Atlantic University in Boca Raton.

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Over his years of research, Kajiura has learned thousands of blacktip and spinner sharks migrate each winter and early spring south into the waters of South Florida.

They stay for a couple of months on a sharky sort of spring break, if you will. By April and May, the sharks begin their migration back north along Florida's beaches, heading as far as North Carolina's Outer Banks for the summer.

Last year, Kajiura reported a spring migration with a much lower average number of sharks, but that trend seems to have reversed itself this year, according to his observations.

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What makes them move? What triggers this shift in biomass? Those mysteries are still being unlocked by shark scientists, but the good news is, even in Florida — the shark bite capital of the world — the number of shark bites on humans in the winter and spring is few.

Even though, as can be seen in the drone video by Jason Griffeth of Vero Beach, shot along the beach of Fort Pierce Inlet State Park in February and March, sharks are often much closer to those of us who enjoy surfing, paddling, diving and swimming at the beach than we think.

In 2018, according to the International Shark Attack File, housed at the Florida Museum of Natural History in Gainesville, there were 16 unprovoked shark bites in Florida waters, well below the five-year average of 27.4. The previous four years were significantly higher — 31 in 2017; 32 in 2016; 30 in 2015 and 28 in 2014.

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As is usually the case, Volusia County led the state in number of bites with four, down from 10 the previous year. Brevard County was next with three followed by St. Lucie County with two. Surfing and board sports remains the most frequent activity humans who are bit by sharks were engaging in accounting for 53 percent of the bites in 2018.

Follow more of Griffeth's photography and video by following Hydrophilik on Instagram and Hydrophilik on YouTube.

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