After operating briefly in San Francisco Bay, "Anderson" shifted to Long Beach on 21 May, and eight days later, took a departure, ostensibly, for the Hawaiian Islands, in company with her division mates, "Hammann", "Mustin", and "Rowan". The ships soon received a change of orders. They rendezvoused with on the afternoon of 30 May, and soon proceeded down the coast, bound for Panama, as another increment of the Pacific Fleet was withdrawn to augment the Atlantic Fleet in its undeclared war with the German Navy in the Atlantic.