Lütje Hörn means roughly 'little horn' in Low German - a reference to its shape on the old maritime maps. It first appears in a 1576 sailing guide under the name Hooghe Hörn, written down by Frisian pilots who needed to warn captains away from the mudflats southeast of Borkum. For nearly three centuries after that, it stayed off the formal topographical record, showing up only in seafarer's lore. In 1859, Lower Saxon surveyors finally added it to the official maps. By then the island already had a personality: skinny, oriented north to south rather than east to west like its neighbors, and clearly subject to the moods of the Ems estuary. The other East Frisian islands - Borkum, Juist, Norderney, Wangerooge - run roughly parallel to the mainland. Lütje Hörn alone sits at right angles to the rest, swept that way by the currents pushing out of the river mouth.

The arithmetic of Lütje Hörn's twentieth century reads like a slow demolition. In 1891 the island measured 61 hectares. By 1937 it was down to 54, the loss mostly chewed off by ordinary winter storms. In 1957 it still showed 58 hectares above the high-water mark, including roughly one acre of substantial dunes - enough vegetation to anchor sand and keep the place looking like a proper island. Then came February 1962. The great storm surge that flooded Hamburg and killed hundreds along the German coast tore through Lütje Hörn as well, peeling away dune faces and washing out salt marsh. The winter storms of 1989 and 1990 took another bite. By 1987 the island was down to 23 hectares. A few years after that, only 11. By the summer of 2006, NLWKN - Lower Saxony's coastal authority - reported that just 6.5 hectares of Lütje Hörn remained above the mean high-water line. The island had lost roughly 90 percent of its surface area in a century.

Even with so little of it left, Lütje Hörn matters. It belongs to Zone I of the Wadden Sea National Park, the strictest protection category Germany applies. Access requires permission from the National Park Administration, which it almost never grants except to researchers. The reason is the same as for nearly every other small island in this sea: birds. The sandbar offers high ground in a tidal landscape with very little of it - a roosting site for waders and a nursery for terns and gulls during the breeding season. There are no buildings on Lütje Hörn. No lighthouse, no hut, no jetty. The island is an uninterrupted strip of sand and salt-tolerant vegetation, administered by the district of Leer in Lower Saxony as an unincorporated area, meaning no humans live there to govern. The unincorporated status is honest. It is also the only sensible designation for a place that may not exist in a recognizable form in another century.

What is happening to Lütje Hörn is what happens to almost all the East Frisian islands, only faster. The currents in the Ems channel scour the western shoreline and dump sediment on the eastern side, so the entire island shuffles downstream over the decades. Borkum next door has migrated too, but slowly and on a much larger budget of sand. Lütje Hörn started small, and there is little reserve to draw from. Climate models suggest the rate of sea-level rise in the southern North Sea will outstrip the accretion rates that have kept the larger islands stable, and the smaller a sandbank is, the sooner it loses the fight. Whether Lütje Hörn survives the next big storm season, the next century, or the next thousand years - nobody can quite say. For now it remains, off the southeast tip of Borkum, a low strip of pale sand visible only at low tide, a German island that has spent four hundred years quietly walking away.