Great White Shark's Death Cause Unclear

Courtney Sacco/AP Photo

A marine biologist was unable to determine what killed the massive great white shark that washed up on a New England beach this weekend.

State biologist Greg Skomal performed a necropsy on the 1,600-pound male shark Saturday and found no signs of trauma.

The 13-foot shark was discovered early Saturday morning by fisherman Gary Severa on the border of Rhode Island and Massachusetts.

"It was pretty scary standing next to that thing…it made your adrenaline go cause he's stone dead, but my God, it has jaws written all over it," said Severa.

Two nearby beaches - South Shore Beach and Goosewing Beach in Rhode Island - were closed to swimmers following the discovery, which quickly drew a crowd eager to get a close-up of this deadly animal.

"People are always curious, and when you have an unusual situation like this, where a 13-foot great white shark is right there, but it can't bite you. They want to see," said Capt. Niko Chaprales of the Cape Cod Shark Hunters.

Throughout the New England area, it has been a real life "Shark Week" for most of the summer with numerous sightings and close calls.

Last Thursday, seven sharks were spotted off the coast of two other Cape Cod beaches, some just feet from the shore days before the start of the Labor Day weekend.

View: Summer of the Shark

Peter Mottur and his family were enjoying the day off the coast of Chatham, Mass., last week when they came across a great white shark feasting on a gray seal, according to ABC News affiliate WCVB-TV in Boston.

"My daughter spotted a fin off in the distance. As it got closer, it was clear it was a shark," said Mottur.

A man was attacked in July by what is believed to be a great white shark in the waters off Ballston Beach in Truro, Mass. Police said Chris Myers was bit in both legs below the knees in possibly one single, crushing blow.

Three weeks before that incident, a great white shark was spotted trailing a kayaker at Nauset Beach, about 25 miles south of Ballston Beach.

Chaprales says the shark sightings have spiked because of the exploding seal population and that swimmers should be on the lookout.

"If you see seals, there will be sharks, and you have a good chance of encountering one," said Chaprales.

As for the great white's body, it will remain where it is for now.

"There's really no means to move an animal of that size," said Krista Selmi, a spokeswoman for the Massachusetts Division of Marine Fisheries.

The Associated Press contributed to this report.