Until 2018 18,5 km at the river Sauer were searched for mussels.
Overall 2612 live animals and 3545 empty shells were detected.
The proportion of alive animals to empty shells is 43% to 57%
With the use of marked animals and their recapture we estimate the current thick shelled river mussel population to be around 10.000 - 14.000 animals in the river Sauer.