Michael Butler, a 41-year-old Treasure Island resident, was in a canoe with two friends near Treasure Island on Wednesday when it overturned, according to the U.S. Coast Guard.
Butler's friends swam to shore and headed home, but Butler stayed behind and climbed back into the canoe, Coast Guard officials said.
His friends called the Coast Guard at about 6:15 p.m. when they could not find Butler.
The Coast Guard worked with 12 local law enforcement agencies to conduct an extensive search for Butler that covered about 190 square miles, Coast Guard officials said.
A helicopter spotted an overturned canoe near Brooks Island late Thursday afternoon and a responding patrol boat found Butler's body.
An autopsy has been conducted on Butler's body, but the cause of death was still pending this morning, a deputy coroner said.