BIDDEFORD — Volunteers on Thursday helped dissect and remove the carcass of a 7-ton minke whale that washed up on a Horseshoe Cove beach this week.

Lynda Doughty, executive director of Marine Mammals of Maine, a nonprofit group that rescues ocean mammals, said the cause of the adult female whale’s death was not immediately obvious. Her group, with help from staff members of the New England Aquarium in Boston, were conducting a full necropsy of the animal and collecting samples to find out how it died.

“It is still to be determined. We got the report of the animal on Tuesday. It probably died out at sea and came in with the tide,” she said.

A resident of Granite Point Road reported the dead 28-foot whale on a Horseshoe Cove beach, Doughty said. The air was pungent around the whale carcass, and volunteers wore masks, along with gloves and oilskins, as they cut away portions of the animal.

Minkes are the smallest baleen whales in North American waters and can grow up to 35 feet long and weigh as much as 10 tons, according to the National Oceanic and Atmospheric Administration. Minke whales are common in the Gulf of Maine and are the most abundant great whale in the world. According to NOAA, in 2015 the minke whale population in the Gulf of Maine and the Canadian Maritimes was estimated at 16,200 to 20,700 animals.

Doughty said reports about whales, porpoises and dolphins make up about 10 percent to 15 percent of the calls Marine Mammals of Maine receives every year, but it is uncommon to come across a dead beached whale.

“It doesn’t happen too often, but when it does we take the opportunity to find out as much as we can,” she said.

Volunteers working with a local excavating company planned to remove the carcass from the beach Thursday, according to Doughty. The animal’s soft flesh will be composted and the skeleton will be saved for education, she said.

Marine Mammals of Maine more often responds to calls about seal pups that appear to be stranded. The group recently received federal certification for its new short-term care center in Harpswell for animals rescued by its staff and network of 70 volunteers from Kittery to Rockland.