In 1970 the f/V "Bull Moose" capsized within Park waters near Ancon Rock.  Two young crewmen from Seattle were trapped on board and were recovered when the vessel was raised a few days later.  Survivors clung to buoys and stayed close together; they were rescued after 10 minutes in the water.  The strong current caused the vessel to lean over; an unsecured seine skiff on board shifted and pulled the vessel over as it slid off the deck.  Stability issues on small vessels as well as larger ones can quickly lead to disaster.  Flotation devices are minimally a necessity; the more the better.