The warm and welcoming waters of Palm Beach, Florida, are attracting not only humans these days, but also mega-schools of sharks.
Thousands of blacktip sharks have taken up residence off the coast of Palm Beach, part of an annual migration from the Carolinas to warmer waters. Whereas the species would generally settle in the Miami-Dade and Ft. Lauderdale areas, this year they've decided to vacation further north.
Stephen Kajiura, an associate professor at Florida Atlantic University who studies the sensory biology of fish, has been tracking the sharks for eight years and notes that this year's number are lower than previous years.
"Last year, we saw a dramatic decline in the number of blacktip sharks that migrated south. In fact, it was so low that we estimated the population to be about one-third of what we have seen in previous years," said Kajiura in a statement. "We want to make sure that these snowbirds come back to South Florida, because if they don’t, it will have a huge ecological impact in this region."
Kajiura's team uses drones, planes, boats and acoustic devices to track the migration patterns. In past years, they counted as many as 15,000 sharks in one day.
While blacktip sharks are responsible for the greatest number of bites in Florida, none of the encounters have ever been fatal.
“These sharks are pretty skittish,” Kajiura added to ABC News. “So when they see a human, they swim away.”
Editor's note: This article has been updated since it was originally published in February 2016.