CHATHAM, Mass. — Wildlife experts are growing concerned for the safety of a manatee that has been recently spotted in waters off the coast of Cape Cod once the seasons change.

Manatees like this one cannot survive for long in waters colder than 68 degrees. Andrew Jalbert/Shutterstock

The 8-foot-long manatee was last seen by a father and son while fishing in Chatham this past weekend.

At least a half-dozen sightings of the mammal have been reported since mid-August. It is believed to have arrived from Florida.

Members of the International Fund for Animal Welfare’s marine mammal rescue and research program were sent to Cape Cod to keep tabs on the manatee, which the organization says has shown no signs of trauma or distress.

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But officials are becoming increasingly worried about the transient manatee if it overstays its welcome. Manatees cannot survive for long in waters colder than 68 degrees. Tuesday’s ocean temperature at Woods Hole was 75.9 degrees.