Large blue whale spotted off coast

Whale watchers got a treat over the weekend: They saw the world's largest mammal make its first appearance in the waters off New England in several years. Naturalists estimate the endangered blue whale to be a true behemoth at about 80 feet long.

The blue whale spotted 15 miles south of Boothbay Harbor, Maine, on Sunday was nearly as long as a pair of 100-foot whale-watching boats that came in for a look.

People aboard both boats cheered.

"I was thinking, 'Wow, this is a chance of a lifetime.' I didn't want to leave because I may never see it again," said Dominique Leclerc, a marine biologist on the Pink Lady II.

Blue whales are found in oceans around the world, but it's unusual to see them off the coast of New England because they prefer the deep ocean farther offshore, said Sean Todd, director of Allied Whale and chairman of marine sciences at the College of the Atlantic in Bar Harbor.

Todd theorized that this whale was off the beaten path following krill, the tiny shrimp-like crustaceans that comprise its diet. The last official sighting in New England waters was three to four years ago, he said.

Because blue whales swim so far offshore, their numbers and activities aren't fully understood. They're listed as endangered under the federal Endangered Species Act, and a previous count of 440 blue whales from the Gulf of St. Lawrence is considered to be a minimum for the northwest Atlantic, Todd said.

Naturalist Mechele Vanderlaan, aboard the other whale-watching boat, the Harbor Princess, said it was only the second time in 21 years that she's seen a blue whale.

"I can't get the smile off my face," she said.

This apparently was one mellow whale. It didn't respond to cheers from people on the boats or the rumbling diesel engines; instead it appeared to be logging, or sleeping.

The massive mammal stayed about 10 feet below the surface, coming up every five to eight minutes to send a shower of water skyward from its blow hole and take a breath before going underwater.

Whales don't sleep the way humans do. While scientists don't fully understand sleep patterns, it's believed that one hemisphere of the whale's brain sleeps while the other remains alert, like other marine mammals, Todd said. Thus, the whale was aware of the boats but was apparently unconcerned by their presence.