Dozens of dead turtles have been washing up on beaches along Flanders Bay— with little explanation as to what is killing them.
The bloated bodies of dozens of diamondback terrapins, a species of turtle that can be found in coastal wetlands along the East Coast, have been found scattered across the shores of several Jamesport and Flanders beaches since late April.
“A woman called who said her daughter had seen a hundred turtles dead on the beach,” said Jim Divan, Riverhead Town Bay Constable. “I was like — a hundred turtles? That sounds crazy.”
But when he arrived at the beach, residents there told him they’d taken “about 100 of them” from the beach over the weekend.
“I’ve never seen anything like it,” Divan said. “They were all dead.”
“We’ve just been getting more and more calls every single day,” said Karen Testa, executive director of Jamesport-based Turtle Rescue of the Hamptons. Testa has collected the bodies of at least 50 terrapins since April 21, when the first report came in.
“And that’s just the ones that happen to wash up, the ones we happen to find,” Testa said. “People don’t walk the entire shoreline of the island. These turtles could be dying in the middle of the bay, and they just float down to the bottom and no one ever finds them.
“It was a horrendous sight,” she added sadly. “All those animals just washed up on the beach.”
Testa’s all-volunteer organization has been collecting any bodies that have been reported, sending them off to a pathologist at Cornell Cooperative Extension of Suffolk County to be necropsied. “Their bodies are in perfect condition,” Testa said. “No lacerations, nothing. They’re bloated when we find them, but that could be due to drowning.”
Just today, another report of dead turtles at the Iron Point sandbar in Flanders drew the New York Department of Environmental Conservation to the area.
“I’ve never seen them die in piles like this,” said William Caldwell, the bayman who transported a DEC technician to Iron Point this morning.
Iron Point is a long sandbar that juts out into Flanders Bay, the main body of water where the turtles seem to be dying off. The sandbar is inaccessible by car, so Caldwell ferried DEC wildlife technician Nick Mancuso to the area this morning in a motorboat.
Together, they brought two of about a dozen turtle bodies from the beach to send back to the DEC for necropsies.
“This place isn’t healthy anymore,” Caldwell said. “This used to be a great spot for clams. We could come in here and catch hundreds of bushels of steamers a day, but there hasn’t been a single one around for years. Something’s out of whack somewhere.”
Diamondback terrapins have one of the largest ranges of North American turtles, spanning from Florida to Massachusetts. After they were hunted almost to extinction in the 20th century due to their popularity as a delicacy in turtle stews and soups, they are now recognized as an endangered species in Rhode Island, a threatened species in Massachusetts and a species of concern in six other states — but not including New York.
New York does regulate the harvesting of terrapins, however; in 1990, an open season for hunting terrapins was established between August 1 and April 30.
The DEC is investigating the cause of this massive die-off, but Kevin McAllister, former head of Peconic Baykeeper organization and founder of Defend H20, speculates it might have something to do with a contaminated food source.
“I’d have to say that would have to be the main factor in a die-off this large,” he said.
Last week, the DEC found elevated levels of the marine biotoxin saxitoxin in local shellfish, prompting the state to close Shinnecock Bay, Meetinghouse Creek and Terry Creek to shellfish and gastropod harvesting. High levels of saxitoxin in shellfish, when consumed by humans, can cause paralytic shellfish poisoning, an acute and potentially severe illness.
Shellfish and gastropods are a main food source for diamondback terrapins.
“It’s very likely that by consumption of the shellfish, the turtles are being poisoned and dying off,” McAllister said.
Saxitoxin is produced mainly by harmful algal blooms, commonly known as “red tides” or “brown tides,” according to the DEC. It causes paralytic shellfish poisoning in humans who have consumed shellfish contaminated by the biotoxin.
Algal blooms have become “almost an annual occurrence” in the Flanders Bay area, according to McAllister.
“It might not be occurring at a density to pose a public health risk,” he said, “but lower densities taken up by the shellfish, which take the toxin in through filter-feeding, could potentially threaten the turtles.”
He emphasized the significance of what 50 dead turtles could mean to the diamondback terrapin population. “That’s a lot of animals, when you consider the population size,” he said. “It’s somewhat rare when you’re out in the field to see a group of them together, so the occurrence of seeing groups of them like that — dead— well, that’s very disturbing news.”