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Researchers encouraged by thriving great white shark population

The migration of great white sharks happens every year. Researchers say even more are making their way to the Florida coast.
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Great white sharks are at the top of the food chain in our oceans. They were once feared, misunderstood and a mystery. Now, there is intrigue and excitement about what's happening off the Florida coast.

"I've really seen a big change and a recovery of the shark populations in our area," Tony Grogan, who has researched sharks for 20 years, said.

Weeks ago, a Florida diver captured a juvenile great white near the Florida coast. 

It added more data to a growing narrative that Bryan Franks with Jacksonville University has seen more clearly than anyone.

"I think in some ways these white sharks have always been here," Franks said. "We just now know more about them by being able to track their movements."

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Franks works with OCEARCH and has been tracking the movements of great whites for the last six years. His data from their expeditions have been invaluable.

"This has traditionally been an overwintering area for them, through our data, as well as other researchers, we can kind of show that they do behave a bit like snowbirds," Franks said.

OCEARCH finds more great whites in northern latitudes, like New England and Canada in the late summer and early fall. As the water cools, they head south for six months, traveling all the way to the Carolinas, around the peninsula of Florida and into the Gulf of Mexico until late spring. It's a cyclical pattern that happens every year.

"One thing we have found is that these animals show fidelity, meaning they do return, if not to the exact same area, but they definitely seem to show preference," Franks said.

In fact, OCEARCH has tracked great whites returning to the same spot within a half mile, and each one is unique. 

Take for instance a shark named Hilton. He was the first one that they tracked bypassing New England and going straight to Canada. Now, 30 great whites have been tracked going back there. 

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Ironbound, a 12-foot 1,200-pound male, pinged recently off the coast of Boca Raton.

"What their population size is, I can't say," Franks said. "I don't think we know that yet."

Franks and OCEARCH have approximately 80 great whites tagged in the western North Atlantic Ocean. 

Twenty projects are underway, with 60 researchers honing in on everything from migration and ultrasounds to skin samples and blood samples. 

The idea is to maximize the amount of info from every single animal to better understand their growth, behavior and migration. Researchers want to know not just where they're going but why.

"I think what we are starting to see is maybe what the oceans looked like 100 years ago, 150 years ago, and I think that's a good thing because a healthier shark population reflects a healthier ocean," Franks said.

This article was written by Jay Cashmere for Scripps News West Palm Beach.