The Untersee is a large shallow lake situated on the course of the River Rhine, adjacent to Swiss IBA 014. Habitat-types include riverine forest, Alnus swamp-forest, dry grassland, wet meadows, lightly improved grassland, shallow water zones, reed- Phragmites and sedge-beds, mudflats and gravel-banks.
This is an important stop-over site for passage wildfowl. Species of global conservation concern that do not meet IBA criteria: Aythya nyroca (breeding).
BirdLife International (2020) Important Bird Areas factsheet: Untersee of Lake Constance. Downloaded from http://www.birdlife.org on 04/07/2020.