Built in 1970, by Fredeman Shipyard Incorporated of Carlyss, Louisiana (hull #106) as the James W. Crawford for the Port Arthur Towing Company Incorporated of Port Arthur, Texas.
The tug was later sold. Where she was renamed as the Miss Heather.
In 1993, the tug was acquired by Hollywood Marine Incorporated of Houston, Texas. Where she was renamed as the Mark L.
In 1999, she was acquired by the Kirby Corporation of Channelview, Texas. Where the tug retained her name.
Powered by two, Caterpillar D398E diesel engines. With Caterpillar reduction gears, at a ratio of 3.84:1. She is a twin screw, towboat, rated at 1,900 horsepower.