BAR HARBOR — A female blue whale seen on Bar Harbor Whale Watch tours last week was a first for the company in its 33-year history. Meanwhile, more sightings of the rare sperm whales seen last week added to the excitement.

Captains Larry Nuesslein and Thomas Bell were in command Sept. 24 for the first sighting of a member of the world’s largest animal species on a tour from Bar Harbor. Naturalist Jessica Damon, a College of the Atlantic graduate, was on the trip along with an intern taking photographs for Allied Whale’s research. Photos of the blue whale were quickly distributed to researchers, who identified the mature female whale as B353, first seen in the St. Lawrence in 2000. Blue whales are identified by distinctive patterns on the side of the body.

“As soon as I got pictures, I got on the phone with the Mingan Island Cetacean Study (MICS) in Quebec,” said Michael Fishbach, executive director of the Great Whale Conservancy (GWC). “They curate the northwest Atlantic blue whale catalog.” The catalog includes 350 individual blue whales, of the estimated 10,000 extant.

Fishbach praised the collaborative effort that included the Bar Harbor Whale Watch, Allied Whale at College of the Atlantic, MICS and the GWC. “This is a really good, a very quick, collaboration that happened,” he said.

Word of the blue whale spread quickly around town Thursday evening and Friday morning.

Jill Weber, a Bar Harbor resident and adjunct professor at COA, was teaching a botany class Friday morning, she said, when one of her students came to class and said, “Did you hear they saw a blue whale?”

“By the time class was over, I had decided I was not going to go to my other job that afternoon,” Weber said. “Class ended at 11, and Friday’s whale watch trip left at noon. I ditched my car, got a winter coat and headed down to the dock.”

The Friday trip, led by captains Brian Silverman and Kevin Moody, headed back to the location where the blue whale had been spotted the day before, in deep water not far from the Jordan’s Basin weather buoy.

“There was a massive footprint up on the water ahead of us,” naturalist Zack Klyver said. The “footprint” is an area of smooth water caused by water being pushed to the surface from the surfacing whale. Then they saw a distinctive blue whale blow.

“We were all super excited,” Klyver said. “A couple of times, it came up within 100-200 feet of the boat. We could see a lot of whale. It was on the smaller side as blue whales go, but still it was probably 70 feet. It never fluked [lifted its tail] but did arch its back up pretty high out of the water. It would come up for 4-7 breaths then dive down. She seemed to be feeding; you could see the water spilling out of the baleen.”

Weber said she was moved to tears being in the presence of the whale. “Even as a plant person, when I saw that thing, the largest animal on earth, it was just so moving. When it spouted, we were inhaling the air that it had exhaled. I thought, ‘Why am I lucky enough to be here?”

On the way back toward Bar Harbor, the group also saw one of the sperm whales that had been spotted last week in the same area. The sighting of the sperm whale was only the sixth in the whale watch operation’s history. “I’ll probably never see one again, even if I live a long life,” Weber said.