Off the South Florida coastal waters, Chessie the manatee, whose name stuck after a 1994 rescue from the Chesapeake Bay, has gone missing after he managed to ditch his fourth tracker in his 35-year lifespan. Officials say the getaway was likely abetted by an alligator chomping on Chessie’s floating GPS tracker. Alligators do not target manatees themselves, just the tracker, which is attached to a 4-foot tether made to come apart if it snags on something.