Move over, Harvard Square turkey. There’s a new visitor in town.
A seal was spotted Monday morning swimming in one of the Charles River Dam’s locks, just below the Leonard P. Zakim Bunker Hill Memorial Bridge, according to officials from the Massachusetts Department of Conservation and Recreation.
“He seemed in a pretty good mood, floating around,’’ said Kevin O’Shea, a DCR spokesman.
Workers from the agency snapped pictures of the curious animal, who stared back up at them with its black eyes, before contacting experts from the New England Aquarium.
Tony LaCasse, a spokesman for the Aquarium, said that, based on the photographs, the animal was an adult harbor seal in healthy condition and looked “robust’’ from feeding.
LaCasse said the seal likely slipped into the Charles by following a school of spawning fish toward the entrance of the dam and then through the lock system.
It may not be the seal’s first time taking a dip in the Charles, officials say. An animal thought to be the same seal has been a familiar face in the area over the last 10 days.
On April 1, employees from the Museum of Science first spotted the seal. Three days later, they again witnessed the animal cruising around in the water. Bewildered but intrigued, the museum reached out to Aquarium officials.
LaCasse said that since then the Aquarium has received a handful of reports about a seal swimming up and down the river. He said the seal has been spotted as far away as the Boston University Bridge, and bobbing near the boats docked by MIT.
LaCasse said it’s possible that the seal has been making multiple trips through the dam’s locks, finding that the carp, bass, and perch in the river are plentiful — and easier to catch than fish in the ocean.
“What we think is happening is that we have a harbor seal that has extended his range, and come to understand there’s easy freshwater pickings on the other side of the dam,’’ LaCasse said. “There are a lot of one-pound-plus fish that are the biggest fish in the river. When you get to that side, it’s literally, for him, like shooting fish in a barrel.’’
The seal’s Monday visit was seemingly short-lived. At about 2 p.m., at the request of Aquarium officials, workers from DCR opened up the Boston Harbor side of the dam and let the seal swim out and head back into the ocean.
But officials said there could come a day when the seal sneaks through again. “Seals are smart,’’ LaCasse said.
This isn’t the first time a seal has made its way into the river from the harbor. In 2010, a seal was seen in the river in the days before the annual Head of the Charles regatta. After a few days, the seal left the area when DCR opened up the dam, officials said.
Steve Annear can be reached at steve.annear@globe.com. Follow him on Twitter @steveannear.
