The two mariners left Weno Island en route for Tamatam Island in an 5.5m vessel over a week ago with "limited supplies and no emergency equipment".
When the two men failed to arrive at their destination a day later, a search effort was launched in the western Pacific on August 19, according to a statement released by the US Coast Guard in Guam.
In recent days, crews from Coast Guard District 14 - which covers the Hawaiian islands, Guam, American Samoa and the Saipan area - searched nearly 44,030 sq km using 15 boats and two aircraft, the statement said.
They had their work cut out for them.
"The Coast Guard 14th District covers an area of responsibility more than [31.5 million sq km] of land and sea, an area almost twice the size of Russia," Jennifer Conklin, search and rescue mission coordinator at the Coast Guard Command Centre Honolulu, said in a statement earlier this year.