Built in 1974, by Halter Marine Services Incorporated of New Orleans, Louisiana (hull #464) as the Mister Bob for the Jackson Marine Corporation of Houston, Texas.
The Jackson Marine Corporation was owned by the Halliburton Corporation of Houston, Texas. The company owned a total of ninety vessels. Consisting mainly of offshore tugs, and supply vessels. With some chemical transport and well stimulation vessels.
In 1985, Zapata Marine Service, Gulf Fleet Marine Incorporated, and Jackson Marine Services merged to form Zapata Gulf Marine Service Incorporated of Houston, Texas. Where the tug retained her name.
In 1989, the tug was acquired by Seabridge Incorporated of Piti, Guam. Where she was renamed as the Chamorro.
She is a twin screw tug, rated at 1,700 horsepower.
(Captain Eric Takakjian, Kyle Stubbs)