The dead finback whale that has been drifting through Boston Harbor made a brief visit to the shores of Georges Island over the weekend before floating back out to sea, officials said.
As of Monday morning, the 50-foot whale “appears to have washed out of channel out to sea,” said SJ Port, spokeswoman for the Department of Conservation and Recreation. She said the high tides and westward winds helped moved the animal’s remains out of the harbor area and they currently cannot be located.
After the whale carcass had washed up on Georges Island, which is under the jurisdiction of the conservation department, officials there began putting together plans to dispose of the remains, Port said.
“It’s like a reverse lottery. It can be a big cost for whoever that property belongs to,” she said.
Preliminary figures estimated the whale’s removal to cost about $30,000, and because it is an endangered species, removal efforts must be approved by the National Oceanic and Atmospheric Administration.
“Sometimes if the body is in better shape, you can attach a hook and rope to pull it into deep water,” Port said. “This carcass is severely decayed at this point. It would fall apart.”
New England Aquarium veterinarians visited the finback while it was on Georges Island to obtain updated measurements, said aquarium spokesman Tony LaCasse.
But plans to dispose of the whale became moot when the body drifted out to sea. The aquarium team was then unable to perform a necropsy to determine a cause of death.
Officials had been concerned about the finback’s presence in the harbor, particularly if it had continued to deteriorate. Various organs that are used to withstanding water and acid, like intestines, could pose problems to boaters in the harbor, Port said.
“If he comes back to us, that will be the next problem,” she said.
Finback whales are the second-largest species of whale. Adults can weigh up to 40 tons and can grow to an average length of between 45 and 70 feet. There are an estimated 60,000-100,000 fin whales worldwide, according to the Whale Center of New England.