A 52-year-old man's body was pulled from the Niagara River near the docks at the Buffalo Launch Club on Grand Island on Sunday night, according to the State Police.
Foul play is not suspected in the man's death, said Trooper James O'Callaghan.
A family member called police when the man could not be located. His boat was docked at the club, O'Callaghan said.
The body of the man, whose identity was not disclosed, was found submerged in the water about 20 feet from the boat.
Authorities aren't sure if the man drowned or if he suffered some type of medical emergency before falling into the water. Investigators are awaiting results of an autopsy conducted Monday, O'Callaghan said.