RedactedNarrative: Vessel 1 was dead-headed on the beach with anchors attached when the Owner/Operator left the area at 2:30 p.m.  When the Owner/Operator returned to the area at 6:00 p.m. he noticed damage to the port aft corner of Vessel 1; specifically, that the aft port side panel/rail was dented in on the corner.  There were no witnesses as to how the damage might have occurred.