Diana wanted to see Tangier Island, so we drove across the Bay Bridge Tunnel and up the Eastern Shore to Onancock, a tiny little village on the Bay. We took the ferry, which is a converted oyster boat, which makes one round trip a day, to the island. We passed quite a few osprey nests on the channel markers; once we were away from land, there were a few fish, plus passing boats and the occasional small island.
The island is pretty much as described in Wikipedia, There's a house which has been converted to a museum on the history of the island and some of the notable residents (or servicemen who signed up and left the island), The main thing is that in one day, you probably can't see absolutely everything; but you can easily walk around the island and see a representative sample of everything. For instance, you can visit one seafood restaurant rather than all of them--but "seafood" is the only kind of restaurant you'll find, except for Spanky's ice cream parlor. Take bug spray and sunglasses and comfortable walking shoes and spend a day.