WPTV reported Wednesday that marine biologists have seen tens of thousands of sharks from Boca Raton to Jupiter since the start of the month. They say the marine animals are moving north as a part of the annual migration, after going south for the winter.
Researchers at Florida Atlantic University say they have now counted some 15,000 sharks. Most of them were seen less than 200 yards from shore.
Spinner sharks can be seen jumping out of the water and spinning, as they chase their prey through the water.
As a precaution, many beaches are on high alert, with double red flags waving to keep swimmers out of the water until further notice.
"People really need to heed these warnings because thank god it's a public beach, and they have lifeguards and they have these warnings," beachgoer Elizabeth Horowitz said. "Sharks are not to be reckoned with."
Blacktip sharks only account for 20 percent of unprovoked attacks in Florida. But during this migration, people there aren't taking any chances.
Out of 53 recorded sharks attacks in U.S. waters last year, nearly half (26) occurred off the coast of Florida, according to the International Shark Attack File.
A majority of U.S. shark attacks typically occur off the coasts of Florida, California and Hawaii each year.
Shark habitats vary, but most shark species live on the continental shelf and in tropical reefs. These areas correlate to the areas with the most shark attacks.