In the spring of 1979 "Acacia" was transferred to Grand Haven, Michigan. She was replaced in Sturgeon Bay by the newly launched USCGC "Mobile Bay". Though moved across Lake Michigan, "Acacia" remained responsible for maintaining the same fleet of 220 buoys from Calumet Harbor to Little Bay De Noc. The smaller "Mobile Bay" did not have a crane capable of the work. She did get at least one new job while based at Grand Haven. In 1984, in cooperation with U.S. Fish and Wildlife Service hatcheries and the Michigan Department of Natural Resources, "Acacia" released 400,000 lake trout fingerlings on offshore reefs in Lake Michigan. It was hoped that fish released in the middle of the lake would have a higher survival rate than those released along the shore.