Anti submarine warfare efforts along Atlantic coastline according to the U.S. Joint Intelligence Committee. Daily summary dated 18 January 1942

An item reported that Allied air and naval patrols using all means controlling contacts made with enemy submarines off the Atlantic coastline. Furthermore was the major part of the coastal shipping removed from danger areas. These measures resulted probably in less targets for the enemy submarines and just few confirmed reports of attacks.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary dated 18 January 1942 No. 39