Built in 1976, by Equitable Equipment of Madisonville, Louisiana (hull #1661) as the Pye Theriot for Nolty J. Theriot Offshore of Golden Meadow, Louisiana.
The tug was originally constructed for handling the Anchors for Oil Rigs in the North Sea.
The tug was later acquired by the Marathon Petroleum Corporation of Findlay, Ohio where she was renamed as the Loretta J.
Marathon fitted the tug with a 442(ft) 150,000 bbl barge named the MM-1 (built in 1981, for Marathon Oil by Galveston Shipbuilding, of Galveston, Texas) for petroleum transportation work in the Gulf of Mexico.
In the early 1990's the unit was acquired by the Eklof Marine Corporation of Staten Island, New York where she was renamed as the Yankee.
In 1993, the Eklof Marine Corporation of was acquired by K-Sea Transportation of New York where the Yankee retained her name. Her barge however, was renamed as the DBL 151.
The tug was later outfitted an Articouple coupler system.
In 2011, K-Sea Transportation was acquired by the Kirby Corporation of Channelview, Texas, where the tug retained her name.
She is a twin screw tug rated at 7,200 horsepower, with a fuel capacity of 204,675 gallons.