Built in 1976, by Main Iron Works of Houma, Louisiana (hull #311) as the Ambassador for Interstate Oil Transportation of Philadelphia, Pennsylvania.
At the time, Interstate Oil Transportation maintained two fleets. Their Northeast Fleet or "Green Fleet" which operated in Philadelphia, Pennsylvania. And a Southern Fleet or "White fleet" that operated out of Tampa, Florida.
However in the years that followed many changes came to Interstate Oil, a company called Southern National Resources purchased (also known for a time as SONAT Marine). SONAT eventually sold out to Maritrans Operating Partners LLP.
In 1998, Maritrans's northeast fleet was thinned. Many of vessels were acquired by K-Sea Transportation of New York, Reinauer Transportation (also of New York) Vane Brothers of Baltimore, Maryland and other miscellaneous buyers.
The Ambassador was acquired by K-Sea Transportation where she was renamed the Tasman Sea.
She was later outfitted with a JAK coupler system. She is a twin screw tug rated at 3,900 horsepower, with a fuel capacity of 127,534 gallons.
In 2011, K-Sea Transportation was acquired by the Kirby Corporation of Channelview, Texas, where the tug retained her name.