Thousands of sharks near shore are part of an annual migration of blacktip sharks moving into feeding grounds near Palm Beach, Fla.
Nick Tomecek/Northwest Florida Daily News/AP
Thousands of four- to five-foot blacktip sharks are brushing past America's premier spring break beaches, raising alarm among swimmers and lifeguards but also drawing new attention to a stunning natural phenomena.
An annual migration of a distinct population of sharks begins off the tip of Florida and moves into an area off Palm Beach in February and March, where the sharks congregate close to shore as the offshore shelf narrows – a prime spot for the small baitfish that the sharks feed on.
The sharks are drawing attention for their natural showmanship, as well. They're often seen making spinning jumps out of the water. And thanks to the clear water and white sands of south Florida, they're easy to spot and view, especially for lifeguards from their elevated chairs.
During the annual migration, "they hang onto the coast and follow the baitfish, which makes them super-easy to see, especially when they get brought together in a tight group," says Shari Tellman, a researcher at Florida Atlantic University's Elasmobranch Research Laboratory, or "the shark lab."