St. Marks National Wildlife Refuge St. Marks National Wildlife RefugeStation reference point Piney Island Unit (Open)1,214 acres Aucilla Unit (Special regs)484 acres Newport Unit (Special regs)12,183 acres Panacea Unit (Special regs)18,215 acres Port Leon Unit (Special regs)2,596 acres Wakulla Unit (Special regs)15,299 acres Closed Unit (Closed)40,263 acres