( CNN ) -- Mitchell Guist , a star of the reality TV show `` Swamp People , '' died of `` natural causes , '' a local sheriff in Louisiana said . Assumption Parish Sheriff Mike Waguespack released the preliminary autopsy conclusion Wednesday , although he said final results will not be available for another four or five weeks . Fans pay tribute to 'Swamp People ' star . Guist , 47 , was working to build a houseboat when he appeared to have a seizure and fell backwards in his boat , said Assumption Parish Sheriff Mike Waguespack . He was with another person on the Intercoastal Waterway , about 75 miles from New Orleans , at the time of his collapse . That person , who did not want to be identified , got Guist back to a boat landing , performed CPR and called his wife , who in turn called 911 , said the sheriff . Guist was transferred to the Teche Regional Medical Center in Morgan City , where he was pronounced dead Monday . Daniel Wiltz , with the St. Martin Parish coroner 's office , declined to comment on the autopsy except to say that it was pending . What is 'Swamp People ' ? `` Right now , we 're thinking about him almost every minute , '' said Brian Catalina , executive producer of `` Swamp People . '' `` We 've lost a really important part of our family and a treasured friend . '' `` Swamp People '' is the popular History Channel TV series that chronicles the lives of alligator hunters . Now in its third season , the series is set in Louisiana 's Atchafalaya Swamp , and focuses on Cajun alligator hunters during the 30-day hunting season that the History Channel notes is `` crucial to their survival . '' Guist appeared on the show alongside his brother , Glenn Guist . `` The two were inseparable . These guys were born in the same house that they both still lived in , up until yesterday . They were two peas in a pod for sure . Neither had ever married . They were just as brothers as you could be , '' said Catalina on Tuesday . Soon after news of Guist 's death broke , tributes began pouring in on the brothers ' official fan club Facebook page . `` RIP Mitchell you were one hell of a swamp man and inspired people like me . Prayers go out to Glenn and the Guist family . May his legacy live on , '' read one . `` May the king of the bayou welcome you home , '' read another . CNN 's Joe Sutton contributed to this report .
NEW : `` Natural causes '' is the preliminary autopsy finding . Mitchell Guist died Monday after falling on his boat . `` Swamp People '' chronicles the lives of alligator hunters in Louisiana . `` We 're thinking about him almost every minute , '' said `` Swamp People '' executive producer .