Some unsuspecting beachgoers recently shared the water with a group of about 100 stingrays. The rays swarmed the waters outside of Lani Kai Island Resort in Fort Myers, Florida. In a short video filmed from a balcony above the beach, the rays can be seen moving en masse as many oblivious swimmers splashed about in the shallow water. 

A group of stingrays is known as a “fever,” much like a group of fish is known as a “school.” The fever maneuvers gracefully around the vacationers, at one point splitting into two groups to avoid a young boy and reforming on the other side. Most of the folks in the water with the rays seem unfazed or unaware of their presence, but onlookers watching from the safety of a nearby restaurant were more concerned. 

“That is literally all stingrays!” said Carrianne Conidaris, who narrated the event while her husband, Dana Baquero, filmed it. “Oh people, move! Oh people, move!”

While suprising to witness, it is not uncommon for stingrays to move in fevers like the one shown in this video. Cownose rays, for example, are known to group up and migrate by the thousands. Though their name and propensity to sting when stepped on may strike fear in some, stingrays are generally regarded as docile creatures. They pose more danger to swimmers when they’re hidden in the sand than they do while swimming around in plain sight. 

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The Florida Fish and Wildlife Conservation Commission recommends employing the “stingray shuffle” to reduce the risk of stepping on a ray. The shuffle is done by moving your feet along the seafloor instead of picking them up and taking steps by lifting up your feet.