RIVERHEAD - Scientists say several hundred diamondback turtles recently died in Flanders Bay and washed up in the Riverhead and Flanders areas.
Researchers believe saxitoxin, a shellfish toxin, may be the problem.
Experts say there are red tides and saxitoxin in the shellfish every year, but the levels this year are 10 times higher than they usually find.
READ MORE: News 12 Long Island Environment Stories
The dangers have led the Department of Environmental Conservation to temporarily ban harvesting shellfish in about 4,000 acres of water in the Peconic.