According to statements, victim passed out while sitting on the back of the boat.  Occupants waited for about 15 min before calling EMS because they thought the victim was only sleeping. 

From some of the involved persons it sounded like victim had 3-4 beers and 2 shots of rum that day. That is what the consensus among their group was.

On nearly all persons involved, the odor of alcoholic beverages was present. Most every person also admitted that they had been drinking for most of the day. 

Conclusion is that the victim succumbed to CO poisoning. Contributing factors were alcohol use and location on the boat.
FISH HAVEN