A seal that has spent the past 10 days in the Charles River has been carefully moved back into the Boston Harbor.
Charles River Dam operators were able to lead the seal into the third lock, where they closed the riverside gate.
The dam operators were praised by aquarium officials for effectually relocating the seal.
It is believed that the seal slipped into the river after pursuing fish through the locks.
Staff members from the Museum of Science first reported seeing the seal in the lower basin of the Charles over the course of multiple afternoons. Earlier in the week, the seal was seen as far as the BU Bridge, on the Cambridge-side of the Charles River.
This is not the first time a seal has slipped into the Charles River, which last happened in October of 2010.
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Most seals, including this seal, are saltwater animals and the Charles River is freshwater. While these seals can eat freshwater fish, they cannot stay in freshwater for long periods, as it can severely upset the sensitive electrolyte balance in marine animals used to higher amounts of salt from sea water.