What was found
AIRCRAFT TRANSMISSION OIL PRESSURE ON INTEGRATED INSTRUMENT DISPLAY SYSTEM (IIDS) DECREASING. MADE TURN TO COME BACK TO INTRACOASTAL CITY. EMERGENCY CHECKLIST PULLED OUT AND FOLLOWED. INDICATED PRESSURE WENT DOWN INTO THE RED. LANDING AREA FOUND, AND LANDED THE AIRCRAFT IN MARSH AREA. ON SHORT FINAL, TRANSMISSION PRESSURE INDICATED 20 PSI, UPON LANDING, PRESSURE INDICATED 0 PSI. AIRCRAFT SHUTDOWN WITH NO DAMAGE TO AIRCRAFT, EXCEEDANCES, OR INJURY TO PASSENGERS.