Built in 1967, by Big River Shipbuilding Incorporated of Vicksburg, Mississippi (hull #5) as the Mr. Bryan.
In 1967, the tug was acquired by Tidewater Marine Services Incorporated New Orleans, Louisiana. Where she was renamed as the Ayrshire.
In 2001, she was acquired by the Delta Towing Company of Houma, Louisiana. Where she was renamed as the Delta Ruler.
In 2011, the tug was acquired by the Crosby Marine Transportation Company of Golden Meadow, Louisiana where she retained her name.
Powered by three, Cummins KT 19M diesel engines. With Twin Disc 2/5-14C & 1/5-14B reduction gears, at a ratio of 5.16:1. Turning three, 56(in) by 42(in) by 5(in) She is a triple screw tug, rated at 1,275 horsepower.
Her electrical service is provided by two, 30kW, generator sets. Driven by two, GM 3-71 diesel engines. The tug's capacities are 9,500 gallons of fuel, 200 gallons of lube oil, and 3,000 gallons of water.