Built in 1943, by Everett Marine Ways Incorporated of Everett, Washington as the YTB-290 (Canocan) for the United States Navy.
She was originally built as fireboat replacement for the Navy Base at Pearl Harbor, Hawaii.
In 1959, the tug was acquired by the Pacific Tow Boat Company of Everett, Washington. Where she was renamed as the Sea King.
In 1969, the Pacific Tow Boat Company, and the Foss Launch and Tug Company of Tacoma, Washington were acquired as subsidiaries of the Dillingham Corporation of Honolulu, Hawaii. Operations of the two companies were united under the Foss Maritime name.
In 1976, the Foss Maritime Company renamed the tug as the Iver Foss.
In 1978, the tug was acquired by and individual named Don Etheridge of Juneau, Alaska. Where she was renamed the Tagish.
Powered by two, Enterprise diesel engines. She is a twin screw tug, rated at 1,270 horsepower.