Whale surprises watch tours in Boston Harbor near Logan Airport

“Be mindful that the animal may be stressed or in distress, so to avoid approach and to not make this an opportunity to go see a whale close to Boston."

A 2-year-old humpback whale surprised three whale watching tours in Boston Harbor Tuesday, a sighting that prompted some concern from the staff.

Linnea Mayfield is the naturalist manager at Boston Harbor City Cruises, which partners with the New England Aquarium for local whale watches.

She said the whale was sighted off Castle Island, by Boston Logan International Airport, and even in the Inner Harbor near the Conley Terminal.

“It does make all of us who work in the whale watching world quite nervous because it does put whales at heightened risk of vessel strike and other threats, including heightened stress,” Mayfield said.

She said the whale, identified as Glo-Stick 2022 calf, could have chased prey into the harbor or ended up there due to distress or disorientation.

Per federal law, the whale watching tours had to quickly move to give the whale a wide berth. Mayfield said it appeared disoriented but uninjured.

The whale watchers reported the whale to the National Oceanic and Atmospheric Administration and continued on their tours, Mayfield said.

“If we find a whale in an area where they don’t normally occur, we might stop with them for a few minutes, take a brief look, ensure that the animal seems physically intact, is not entangled in fishing gear or anything like that, doesn’t seem to have any visible, notable injuries, and then we’ll move on,” Mayfield said.

The whale might stick around in the area for a few days to continue feeding or as it finds its way out of a stressful scenario, according to Mayfield.

“They obviously don’t adhere to rules like we do. They don’t have any set standards or boundaries of where they can travel to, so this does occur every few years,” she said. “We don’t see it quite that far in the harbor often.”

But, she said, no one should try to approach the animal.

“Be mindful that the animal may be stressed or in distress, so to avoid approach and to not make this an opportunity to go see a whale close to Boston,” Mayfield said.