Several Japanese warships except aircraft carriers sighted in the Solomon Islands-Bismarck Archipelago according to the U.S. Joint Intelligence Committee Daily summary dated 17 May 1942

An item reported that allied aircraft flying over the Solomon Islands-Bismarck Archipelago area sighted numerous transports, 1-2 tankers and some cruisers and destroyers although since several days were none aircraft carriers seen. Probably was all available air power drawn back by the Japanese probably for an offensive to the north east areas.

Source

Map Room Papers (Roosevelt Administration), 1942 - 1945. U.S. Joint Intelligence Committee. Daily summary No. 158 dated 17 May 1942