Robert H. Uisok, a 36-year-old Alaska Native man from Bethel, was last seen on August 23, 1980, reportedly taking a boat trip from his hometown in the Yukon-Kuskokwim Delta. He was described as 5 feet 7 inches, about 150 pounds, with black hair and brown eyes. When he failed to arrive at his destination or make contact, a search was begun.

Searchers later found his boat run aground in a slough north of Emmonak on the Yukon River; the boat was empty and no further sign of Robert was ever located. Authorities have worked from the working theory that he drowned, but there were no witnesses or definitive evidence to explain what happened, and no trace of him has been found.

Anyone who knew Robert, his routes on the river, or who has information about that stretch of the Yukon River in August 1980 is asked to come forward.