Battle of the Atlantic

Following a Bermuda shakedown, Otter joined the Atlantic Fleet and escorted two carriers to Casablanca, then, for the remainder of the year, she helped protect convoys shuttling from the United States to various Mediterranean ports. Throughout these operations not a single ship was lost.

In December 1944, Otter and three of her sister ships formed a task group to hunt and destroy German U-boats in the middle and north Atlantic. On 16 January 1945, without assistance from aircraft, the group located and sank German submarine U-248. Otter, after playing a crucial role in the depth charge attack, proudly displayed a submarine silhouette on her bridge.

In April, this task group joined a large task force of destroyer escorts and escort carriers patrolling the shipping lanes of the North Atlantic and searching for submarines. During these operations, destroyer escort Frederick C. Davis (DE-136) was torpedoed and sunk, and while other ships of the group engaged and sank U-546, Otter assisted in the rescue of survivors.

Upon the end of the war in Europe, Otter was one of the ships assigned to accept the surrender of German submarines. She intercepted a U-boat east of Newfoundland, put a boarding party on board, and escorted the submarine, the second to surrender, over a thousand miles to the East Coast of the United States.

Otter then began to refit for the Pacific War. The end of hostilities changed plans and Otter was assigned to the Naval Submarine Base New London, Connecticut, to assist in submarine training.

Fate

By directive dated January 1947, Otter was placed out of commission, in reserve, attached to the United States Atlantic Reserve Fleet and berthed in Florida. She was finally sunk as target off Puerto Rico on 10 July 1970.