A manatee was seen swimming in a northern canal that joins the Chesapeake Bay with the smaller and shallower Delaware Bay just days after the marine mammal was spotted in an estuary of the Potomac River.

The docile "sea cow," is normally found in the warm waters of Florida and is a rare sight so far north.

WBOC television says the 7-foot animal surfaced at the Summit North Marina in Bear, near Delaware City. The news station says there was a third sighting earlier this month near Ocean City, Md. "Officials say they are not sure if each sighting is of the same manatee, or if there are several of them in the area."

Cpl. John McDerby of the Delaware Division of Fish and Wildlife is warning boaters to be on the lookout for the animal in the C&D Canal. Boat propeller strikes are the major cause of manatee deaths in the animal's native waters in Florida, he says.

According to The Baltimore Sun:

"Manatees sometimes migrate up the East Coast during the warmer winter months, [National Aquarium] officials said. The sea grasses found in the Chesapeake Bay are an ideal food."While most manatees do not venture as far north as Maryland, the sighting is not without precedent."

The (Delaware) News Journal quotes McDerby as saying that while a manatee was seen in the Indian River inlet just last year, that he can't remember ever hearing of one in the Chesapeake & Delaware Canal.

"It's something you don't see every day," McDerby was quoted by the newspaper as saying.

Speaking with NPR, McDerby said he really doesn't know why the manatee has traveled so far north. He says it's "most likely" that the animal seen in the C&D and the one spotted farther south earlier in the week "are the same animal."

In years past, a male manatee nicknamed "Chessie" was apparently a semi-regular visitor to the Chesapeake Bay. A 2011 Baltimore Sun article reported on a visit from Chessie and noted at the time that the manatee had visited the bay "at least twice over the past 17 years."

While it's possible that one or more of the latest sightings might represent a return of Chessie, it seems unlikely.

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