A 20-foot-long basking shark that appears to be dying has washed ashore on a Long Island beach.

Tracy Marcus of Cornell Cooperative Extension says the shark is likely dying from some kind of illness. There are no propeller wounds that might have come from a boat, nor are there any puncture wounds on the animal, which was barely breathing.

The basking shark, which are a common sight in the waters off Long Island, washed ashore on a town beach a few miles east of Jones Beach. Basking sharks are not considered dangerous. They eat plankton.

Marcus estimates the shark weighs about a ton. She says it is unusual for an ailing basking shark to come ashore. Usually they die in the ocean.