Grassy and solitary on Moriches Bay's wintery horizon, the island beckoned to me like tapping on the windowpane. On paper, too, it intrigued. I traced its perimeter with a finger on the 1956 topographic map. An inconspicuous sand patch just behind the barrier beach in the shallow waters of Moriches Bay, the unnamed island was just close enough to the inlet to challenge the skills of a circumnavigating small boat sailor, but still close enough to home to be reachable in an afternoon sail. And it had no name at all, just the intersection of latitude and longitude in the shadow of the more prominent Swan Island a couple hundred meters west and across the channel. Both were the product of the same dredging campaigns that kept the choppy, tidal Moriches inlet semi-navigable and kept the channels deep enough for larger craft, and the other Long Island inlets, from Shinnecock and beyond, had similar sandy repositories that shared the same origin. But it was my father who suggested one quiet afternoon in early summer that we go out there on foot: under the new moon, the bay at low tide was just under 5 feet deep between Dune Road and the islet, and with a bit of luck we could walk there. We forded the cattails of Dune Road's northern edge and stepped into the Bay, which was still chilly with early summer, striking northward across the channel to the island. The trek took just a few unnerving minutes as the cool waters of the bay rose around us. It was transparent and we took advantage of being able to see the bottom to step gingerly around the sharp mussel beds on the sea floor and avoid the waving beds of kelp that fanned westward in the outgoing tide. Over our shoulders and beyond the barrier beach was the roar of the Atlantic and the thump of waves landing on the shore. Around us the seabirds flew circles in the summer sky. The Peconic Bay ecosystem is as good a place as any to get lost. And for the wildlife that finds itself increasingly pinched in a usually -- booming real estate market, its remaining quiet corners are essential. For that matter, I found myself feeling refreshed as we circumnavigated the sand island, now grassy and even sprouting a young forest thanks to seeds blown in from the mainland. There were piping plovers and terns on all sides of us, and egrets and herons wading in the shallows on all sides. Back on the mainland -- a someone tenuous concept when it's a barrier island to another island -- a family of osprey watched us from their perch. Swan Island, and Not Swan, both began life as sand blown out of the barrier beach by the destructive hurricane of 1938. There will be other hurricanes like it, and they will batter the Long Island coastline like before. Their longevity lies in their very ephemerality. And long after the next hurricane lays waste to recent Hamptons real estate, I suspect a walk around Not Swan will reveal a quiet, avian ecosystem not unlike the one I discovered for myself.