A young beluga whale spotted swimming in Montreal's Old Port since last month is at risk of developing an infection from its new freshwater environment if it doesn't soon find its way home some 500 km away, scientists say.

The mammal, which strayed from its natural salt water habitat in Tadoussac, Que., has already been affected by the change in habitat, said Robert Michaud, the research director of the Tadoussac, Que.-based Group for Research and Education on Marine Mammals.

"The photographs we've obtained from the animal over the last few days suggests he already has some skin problems," Michaud said. "The skin is all wrinkled. He could develop some infection."

The group continues to track the whale's movements and hopes it will not have to intervene to forcible remove it and return it to a salt water habitat.