v-1 was at anchored (line attached to the bow) when the vessels stern began to flood causing it to capsize

On 08-08-2012 Officer and I of the Florida Fish and Wildlife Commission responded to an over turned vessel when we arrived on scene we found USCG, Sea Tow and the operator/owner of vessel FL7776KA onboard a good Samaritan vessel. Operator stated he was on a diving trip ocean side of Key Colony Beach when the vessel took on water and capsized while at anchor.
According to a statement provided by operator, he departed Key Colony Beach on a diving trip with 04 passengers on board. Once there destination was reached they anchored. Operator and his son then began a dive. When Operator resurfaced his brother in law called upon him to inform him that the boat was taking on water. Once he reached the vessel he attempted to crank the engine as he was doing so the vessel capsized. This caused the occupants to go in the water.
Operator also indicated that he could not see the bilge water being dispelled from the through hull. Due to the water conditions, bilge system failure the water in the hull weighed the vessels stern enough to cause water to enter the open transom causing the vessel to flood then capsize.
At this time a near by vessel saw the incident and responded to the scene recovering the 05 individuals from the water. At this time the occupants contacted USCG who contacted FWC. 
The vessel remained on the surface until the air in the bow was expelled the vessel then sank. On 08-10-2012 I confirmed that the vessel was removed and photographed it at the Galloway Bay trailer park in Marathon, FL.

MARATHON                      