Fährinsel consists of a fan of several berms, up to 2 metres high, and spits, as well as silted-up areas of the lagoon, the Schaproder Bodden.
When the ice retreated, the Dornbusch on Hiddensee, as well as two ridges of glacial till running westwards from Rügen, belonged to a vast Young Drift landscape in the southern Baltic Sea region.
One ridge formed the heights of the island of Ummanz and the Gellen peninsula, another ran between Trent via the present Stolper Haken near Seehof northwards from Schaprode to the Fährinsel.
Following the flooding of the region around Rügen and Hiddensee about 3,900 years ago, the aforementioned end moraines remained behind as islands.
When the remaining cliff section on the Fährinsel was abraded, southward running spits formed due to the currents from the northeast flowing past both sides of the northern tip of the island.
The narrow bays, lagoons and runnels (Riegen) between the spits slowly filled with organic material and silted up.
Headlands on the Fährinsel are the Mövenort, no longer recognizable as a spit in the central region, and the Buschort, its southern tip.
During migration periods between March and May and between September and November, waders and ducks gather in large numbers on the meadows and in the shallow bodden waters.
Between 28 June and 10 July 1971 one to four gull-billed terns were observed[1] and on 28 May 1985 an adult rosy starling[2] from central Asia and Southeast Europe stayed on the island.