On Saturday, a leatherback sea turtle weighing 800 pounds was found death off Cape Cod. Now, New England Aquarium biologists are going to perform necropsy on the six-and-a-half foot long turtle to know the reason behind death.

The adult female, which was found around a mile south of Wood's Hole by the Massachusetts Environmental Police, was having a two foot section of marine rope in her mouth. It is considered that the turtle had died two days back.

After spotting the dead turtle, the Massachusetts Environmental Police, towed it to a boat ramp near the Woods Hole Oceanographic Institution. Marine biologists have affirmed that the necropsy would take place on Sunday at the New England Aquarium Sea Turtle Hospital in Quincy.

Aquarium spokesperson Tony LaCasse said that this one is the first sea turtle, which did not have a hard shell. LaCasse affirmed that generally, these turtle migrate to New England waters in early summers so they can feed on sea jellies.

"With water temperatures in the 50's, the last of the leatherbacks should be migrating out of the Gulf of Maine, swimming south past the Cape and the Islands and then down the eastern seaboard to the eastern Caribbean for the winter", added LaCasse.

The turtle was found Saturday by Massachusetts Environmental Police about a mile south of Woods Hole.

Leatherbacks are the largest turtles and one of the largest reptiles in the world, the aquarium says. They migrate into New England during the summer to feed on sea jellies and usually winter in the Caribbean.

The soft-shelled turtle was discovered by state Environmental Police and towed to the Woods Hole Oceanographic Institution, where it was slipped into a heavy duty nylon stretcher specially designed for marine animals.

Dock master Eric Handy then used an industrial forklift to load the leatherback into an aquarium vehicle, LaCasse said.

As per initial observations made by New England Aquarium biologists, the turtle might have died by getting entangled with a vertical line. On its body, biologists have found abrasions and tissue tearing and marine gear entanglement.