After the boat sank Friday near Galveston, rescue crews scoured about 5,400 square miles -- roughly the size of Connecticut -- with helicopters, planes and boats, NBC News reported.
The Coast Guard said after it got notice of the incident, a jet aircrew was launched from Air Station Corpus Christi to get an overflight of the area and saw a man, John Reynolds, waving his arms aboard an orange raft. A rescue team hoisted the man to safety.
Reynolds said there were four other crewmembers aboard the boat before it sank. He was taken to a nearby oil rig to check out any medical concerns and to permit the helicopter crew to resume their search.
"When it comes to canceling a search-and-rescue case, that's really up to our search-and-rescue coordinators. They base a lot of factors into calling off a search, including water temperature, wind speed and the number of people missing," said Coast Guard Petty Officer Richard Brahm.
The four missing fishermen were not identified. NBC News said it was not clear what caused the boat to sink.
Brahm said: "The guy that we rescued just said the boat started sinking. He wasn't sure what caused it. That will be part of the Coast Guard investigation."