NOAA Ship McArthur was built by Norfolk Shipbuilding and Drydock Company in Norfolk, Virginia. Commissioned on December 15, 1966, the ship conducted oceanographic research and assessments, primarily throughout the Exclusive Economic Zone of the U.S. Pacific Coast. The 175-foot ship measured chemical, meteorological, and biological samples for several large scale programs within NOAA. The majority of McArthur's work was done in several of the National Marine Sanctuaries on the west coast of the United States. The ship was homeported at NOAA's Marine Operations Center—Pacific in Seattle, Washington. The ship was named after William Pope McArthur, and she was succeeded by the NOAA Ship McArthur II.

McArthur accommodated 6 officers, 17 crew members, and up to 13 scientists. The scientists who carried out research aboard the ship came from several federal and state government agencies—including NOAA—and academia. The ship supported a wide range of studies, such as the Chase Encirclement Stress Studies where scientists surveyed marine mammals throughout the eastern tropical Pacific. McArthur was also involved in the Sustainable Seas Expedition and the Oregon, California, Washington Project to support protected and non-protected species research efforts.