Great white shark washes up on beach between Westport and Rhode Island

Officials could not determine a cause of death for a 13-foot adult male great white shark that washed up on the border between Westport and Little Compton, R.I., this morning, officials said.

“It will probably remain a mystery,’’ said Dr. Greg Skomal, a marine biologist with the of the state Division of Marine Fisheries.

The dead shark was found in the surf near Goosewing Beach around 8:30 a.m., said Sergeant Steven Criscione of the Rhode Island Department of Environmental Management.

The shark likely died less than a day before washing ashore, he said. No signs of fishing hooks or foul play were discovered, Skomal said.

“The problem is the animal was so badly abraised by sand and rocks that it’s hard to tell if it’s had any interaction with fishing gear,’’ he said.

In a four-hour field necropsy, Skomal determined the shark had an empty stomach and no obvious signs of trauma. He speculated the shark may have been caught in fishing gear. Fishermen are legally prohibited from carrying sharks to shore and usually release them into the current if they accidently catch them in their nets.

Great white sharks have been swimming off Massachusetts coasts all summer, attracted by seals they prey upon.

“On average, in general, we have noticed a trend upward,’’ he said.

On Friday, two great whites were tagged near Nauset Beach in Orleans, bringing the number of sharks tagged off Massachusetts to at least 11 this summer.