On Sanibel Island, the JN Darling Nat. Wildlife Refuge takes up a sizable fraction of the island. The Ding Darling Drive is a great way to see shore birds. The merganser was in one of the larger lagoons.
The Corkscrew Swamp Sanctuary is always a great place to visit. Most of the attention was to the watery swamp on one side of the boardwalk. Yet there was often activity behind us. This wren is a case in point.