The large sea mammals usually don't swim that far north.
A wandering manatee was found in the Chesapeake in the mid-1990s and was nicknamed Chessie.
He was captured and flown back to Florida because scientists were worried he might not make it on his own when the weather turned cold.
Chessie was outfitted with a radio transmitter.
Scientists followed his travels for years up and down the East Coast.
The Coast Guard is now urging boaters to keep an eye out for the manatee so they won't hurt it.
