Built in 1953, by National Steel and Shipbuilding Company of San Diego, California (hull #222) as the LT-2075 for the United States Army.
In 1992, the tug was acquired by the American Navigation Company of San Francisco, California. Where she was renamed as the Marauder.
In 1994, the American Navigation Company renamed the tug as the Marine Exporter.
In 2005, the American Navigation Company was acquired by the Foss Maritime Company of Seattle, Washington. The company became AmNAV Maritime Services of Oakland, California. A subsidiary of the Foss Maritime Company of Seattle, Washington. Where the tug retained her name.
In 2006, the tug was transferred to the Foss Maritime Company subsidiary. The Constellation Maritime Company of Manchester, Massachusetts. Where she was renamed as the Cygnus.
In 2010, she was acquired by the Krause Marine Towing Corporation of Perry Hall, Maryland. Where she was renamed as the David M. Krause.
Rebuilt in 2006, she is powered by two, EMD 16-645 turbo diesel engines. For a rated 5,000 horsepower.
The tug's capacities are 35,000 gallons of fuel, 400 gallons of lube oil, and 3,250 gallons of water.