Rheindelta Nature Reserve

The Rhine enters Lake Constance through a delta of about two thousand hectares of reed bed, shallow water, gravel and wet meadow on the Vorarlberg shore, and it is a Ramsar site and the most important bird area in the province - over three hundred species recorded, with large numbers of wintering ducks and geese, breeding reed warblers and bitterns, and heavy passage of waders in spring and autumn. The delta is still building: the Rhine was channelled into its present mouth in the early twentieth century and the sediment it carries is pushing new land out into the lake year by year, which is unusual to be able to watch happening. Paths and cycle routes run along the edges with hides; the core zones are closed and boats are restricted in the breeding season.

History

When the Rhine glacier withdrew after the last glacial period, Lake Constance formed, reaching further south up the Rhine valley than today, and at the same time the river began building its delta at the mouth of the Alpine Rhine. The process goes on today, and in several thousand years it would end with the lake silted up altogether (Wikipedia, Rhine Delta - Lake Constance).

Highlights

• A building river delta - new land pushing into the lake as sediment arrives.
• Over three hundred bird species - wintering wildfowl, breeding reed birds and passage waders.
• Reed beds and shallow water - the two thousand hectares of the reserve.
• Hides and edge paths - the access, with core zones closed to entry.

When to go

March to May and August to October for migration; winter for wildfowl. Half a day.

Good to know

Core zones are closed and boats restricted in the breeding season - you watch from the edges. Binoculars are essential. It is flat and exposed with little shelter. Mosquitoes in summer.

Nearby

Bregenz and its lake stage are east; Switzerland is across the water.

Key facts