DENNYSVILLE – The 24-foot basking shark that died in the Dennys River was probably hit by a propeller blade in deeper water, then wandered into the Down East waterway, according to a marine biology professor.

Gayle Kraus of the University of Maine at Machias said a round piece of the snout – approximately the circumference of a football – was missing. The cut was jagged, which indicated it had been ripped out by a propeller, she said.

“I’m afraid the poor animal died over a period of days from infection and loss of blood,” Kraus said.

Beth Mills of Dennysville said she and her husband, Maurice, saw the shark struggling in the river last Wednesday night, about a mile and a half from where its body was found Thursday.

The couple didn’t know the animal was injured and thought it was trying to move out to deeper water with the outgoing tide, Mills said.

Someone else saw it earlier in the week, Mills said, and several people told her that a basking shark had come up the Dennys about 20 years ago.

Kraus said Jim Hall, a fisheries biologist with the Maine Department of Inland Fisheries and Wildlife, called her Thursday and asked if she could go to the River Road site and identify what type of shark it was and how it died.

Kraus said she and 12 of her students found the animal on the riverbank partially submerged.

“She was lying on hard ground,” Kraus said. “Basking sharks don’t have swim bladders, so they don’t float like fish do when they die.”

The shark, which was an otherwise healthy female, was 24 feet, 4 inches long and probably measured 15 feet around at its widest point. Kraus said she and her students couldn’t roll the animal over, so they had to do a partial measurement of the width and calculate the remainder. The shark probably weighed 2 to 21/2 tons, Kraus said.

Kraus and her students cut the shark open, but didn’t find any pups, she said. They took samples of the gill, skin, liver and ovaries. Those tissue samples, which are frozen, are available to anyone who wants to run toxicology tests, she said.

Kraus said basking sharks are quite common in the Gulf of Maine. Kraus said she saw two live animals on the east side of Grand Manan Island, New Brunswick, on Sept. 9, and they are frequently seen at Head Harbor off Campobello, New Brunswick.

“They swim near the surface of the water because they feed on plankton,” she said. “They just follow the plankton.”

There is no way to remove the body of the shark from the Dennys because the river is too shallow to bring in a large boat. If no one cuts up the carcass and carries it away, the shark’s body will decompose over the winter, Kraus said.

Kraus said she’d like to salvage the skeleton and put it on display at the university for visiting grade school pupils.

“It would be a wonderful resource and we do a lot of public school tours up here,” she said.