Marine biologists are trying to figure out why so many sea turtles have been found freezing along the Northeast coast, including some on Long Island.

The Riverhead Foundation for Marine Research is treating nine endangered Ridley sea turtles after they were all found "cold-stunned," or trapped in waters that are simply too cold for them to live in.

"As their body temperature lowers, all their systems start breaking down, their heart rate and respiration," says Kim Durham, of the foundation.

One such turtle was found by Dave Anschel, of Rocky Point. He was taking a nighttime stroll at the beach by his home when he spotted a turtle in the sand. "It was bleeding from the shell, and pretty beat up," Anschel recalls. "It was barely moving." The turtle is now being treated for pneumonia and frostbite by the Riverhead Foundation.

Experts say the turtles begin their lives in Mexico, and every year they migrate as far north as New England before heading back South when the weather turns cooler. It's not uncommon for some of the turtles to get caught in local bays and in the Long Island Sound, but there has been a record number of strandings in New England in recent weeks, and researchers worry it might happen around Long Island as well.

"This year is unprecedented," Durham says. "Over 1,500 animals have stranded in Massachusetts since November -- 60 a day."

Researchers are trying to figure out why it's happening, but they say the more immediate concern is nursing the turtles back to health.

Experts say anyone who finds a sea turtle on a beach should not approach it, but should instead call the Riverhead Foundation's hotline immediately at 631-369-9829.