The Coast Guard Cutter Mackinaw, a 240-foot icebreaker homeported in Cheboygan, Mich., backs down alongside the motor vessel James R. Barker in the vicinity of the Johnson Point Turn in the lower St. Marys River, March 26, 2013. The Mackinaw was backing down in order to break up the brash ice off the ship's starboard side and give the ship's stern room to swing.