Built in 1980, Hunt's Steelship Incorporated of Pine Bluff, Arkansas (hull #168-75-80-(6168) as the Sioux for Apex Oil Company of St. Louis, Missouri.
In 2003, the tug was acquired by American Tugs Incorporated of San Juan, Puerto Rico. Where the tug was renamed as the Marilin R.
In 2004, she was rebuilt and reconfigured with two, EMD 16-645 diesel engines. With Schottel z drives. She is a twin screw tractor tug, rated at 3,600 horsepower.