Many of the turtles were found frozen in water; others washed up on shore. Some of the victims were Kemp’s Ridley turtles, the most endangered sea turtles in the world.
“It was like they were flash-frozen, flippers in all weird positions like they were swimming,” Robert Prescott, director of Massachusetts Audubon’s Society Wellfleet Bay Wildlife Sanctuary, told the Cape Cod Times.
Of 82 turtles discovered frozen Thursday, only one survived, the newspaper reported. A total of 219 dead or cold-stunned turtles were found in the three days ending Friday.
About a dozen surviving turtles have been sent to the New England Aquarium to be cared for there. Others are being treated at the Audubon wildlife center.
Turtles can become trapped in the hook-shaped cape that’s difficult for them to negotiate. The cold-blooded animals’ systems begin to shut down once water temperatures drop below 50 degrees. They become immobilized and are then at the mercy of the wind.
Most of the turtles are from tropical areas and prefer water temperatures as high as 85 degrees Fahrenheit. They are carried north in the Gulf Stream during the summer but must swim back south as the seasons change. Climate change and its warmer ocean water can trick the turtles into lingering too long too far north where a sudden drop in temperature has deadly consequences.
“Sea turtles are moving further north along our coast ... as waters are warming and they are expanding their ranges,” Wallace Nichols, a sea turtle biologist and research associate at the California Academy of Sciences, told NBC. “So when we get these quick swings from warm to cooler, the turtles that haven’t made it south definitely get into trouble.”
Wildlife workers and volunteers began rescuing cold-stunned turtles beginning last month. One of the early turtles to wash up when the temperatures dropped was a 300-pound leatherback that couldn’t be saved. But this week has been the deadliest so far.
Prescott believes the number of turtles stunned or killed by the cold collected by wildlife workers could reach as high as 1,000 by the end of the year.
This article originally appeared on HuffPost.