With the declaration of war, Itasca was reassigned to the Fourth Naval District headquartered at Philadelphia, Pennsylvania, and was refitted for anti-submarine service with the addition of 3-inch rapid-fire guns and a Y-gun for launching depth charges.
When war was declared, Itasca was moved from its previous assignment to the Fourth Naval District based in Philadelphia, Pennsylvania. The ship was then modified to better defend against submarines with the addition of 3-inch rapid-fire guns and a Y-gun for deploying depth charges.