Following shakedown off Bermuda and escort training at Casco Bay, Maine, the destroyer escort reported to Norfolk for anti-submarine duty in the Atlantic off the Cape Verde Islands. She operated as part of a hunter-killer group built around the escort carrier and also composed of , , and . Throughout May, this task group followed up submarine reports, chasing down sonar contacts that usually proved to be fish or debris. On 6 May, "Buckley" rammed and sank an enemy submarine, verifying that the waters of the South Atlantic did hide enemy submarines.