Locals were stunned to see the marine mammal relaxing on a chunk of ice west of the city in Lac-St-Louis on New Year's Eve.
"We were amazed," said Kathleen Kay, two days after she spotted the seal Saturday.
"It was an interesting visitor."
Kay reported the sighting to a marine mammal rescue organization, which received reports again Monday that the seal was seen swimming in the same area.
The group's co-ordinator, Robert Michaud, said the wayward seal probably got lost and swam down the St. Lawrence River from the saltier St. Lawrence Estuary.
He warned that the creature's surprise appearance in the freshwater habitat could actually be dangerous for the seal.
"This is not the best place for a seal to be," said Michaud, who noted that an extended exposure to freshwater can harm a seal, such as damaging its eyes.
"If this animal were to stay there for several weeks, he could end up being in a much worse condition."
So far, he said the seal appears to be in good health.
Michaud said while harp seals are extremely rare near Montreal, his organization usually receives one or two reports about sightings near the city every year.
They rarely assist seals, which exist in abundance on the East Coast, whenever they're stuck this far upriver. In this case, they'll likely let nature take its course, he says.
"Eventually, we hope this animal finds its way back to the ocean, where it belongs," he said.
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