Thousands of sharks near shore are part of an annual migration of blacktip sharks moving into feeding grounds near Palm Beach, Fla. 
 
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 Hunter Mason (l.) and Olivia Murat, on spring break from the University of Indianapolis, relax on the beach Tuesday in Destin, Fla. Thousands of blacktip sharks are brushing past Florida's spring break beaches, raising alarm among swimmers and lifeguards. 
 
 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." 
 
 Ms. Tellman and other researchers have been tracking the blacktip shark migration by Cessna airplane since 2011, trying to understand how climate change – specifically warmer average water temperatures – may affect the migration and the dynamics of the ecosystem. 
 
 "We're looking to see whether [climate change] might shift their migratory pattern north and whether we could lose them as apex predators [in this area], and also whether regulations as far as shark fisheries are concerned are actually working." 
 
 A report from the journal Marine Policy estimates that humans may be killing more than 100 million sharks a year. Tellman says the migration appears to contain fewer animals this year, though the cause of that is unknown. 
 
 Blacktips account for 20 percent of unprovoked shark attacks in Florida, and beachgoers are taking precautions. But blacktips are seen as being less of a threat to swimmers and surfers than tiger sharks, which sometimes prey on the blacktips. 
 
 Florida had the largest number of unprovoked shark attacks in 2012, a total of 25. None were fatal. ||||| (CNN) If you were wanting to escape the winter weather by hitting the warm beaches in Florida, you might want to steer clear of the water. Thousands of sharks are migrating right off the coast of some popular beach towns. 
 
 Florida Atlantic University biological sciences professor Stephen Kajiura, captured video Friday morning of blacktip sharks invading the waters of Palm Beach, on Florida's Atlantic coast. 
 
 The majority of shark bites that occur in Florida are attributed to this species, but there has never been a fatal attack credited to the blacktip shark in this region, according to the National Oceanic and Atmospheric Administration. 
 
 Blacktips, named by the black markings on the tips of their fins, are common in the warm coastal waters around South Carolina to Texas. The feed on fish, stingrays and squids, and have been known to follow fishing boats and feed on culled catches. 
 
 Kajiura started tracking this season's shark migration on January 15, when when the first sharks were first spotted around Miami Beach. Since then he has taken to the skies in to monitor the path of the school of blacktips up the coast. 
 
 "There are literally tens of thousands of sharks a stone's throw away from our shoreline," he told CNN affiliate WPEC . "You could throw a pebble and literally strike a shark. They are that close." 
 
 Every winter, thousands of blacktips migrate along the Atlantic coast searching for warmer waters, this coincides with their mating season. 
 
 If you are wanting to take the plunge in the Florida waters, at this time Kajiura said the majority of the blacktips are swarming in the seas from Palm Beach to Singer Island and up to Jupiter Inlet. 
 
 Kajiura is planning on tagging some of the sharks to help study their migration patterns.
– Thousands of visitors are swarming to beaches in South Florida, but not the kind welcomed by the chamber of commerce: sharks. Their annual migration up the East Coast is taking place later than usual this year, coinciding with the start of spring break season, reports ABC News. Several beaches had to close earlier this week, reports the Palm Beach Post, though all were back open as of today. Researchers at Florida Atlantic University have counted 15,000 sharks so far, most within 200 yards of shore. The most common are blacktip and spinner sharks, about 4 to 5 feet long. But it's not all gloom and doom: "The sharks are drawing attention for their natural showmanship, as well," writes Patrik Jonsson at the Christian Science Monitor. "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."