The objective of the project is to: 1) Find new methods and solutions to stop decline of the sterile mussel population as well as test critical factors for its propagation. 2) Provide updated information about the preservation of the mussel population to both public and private sectors that through their decision-makers and through their activities can influence the situation of the fluvial environment. 3) Expand and deepen Nordic cross-border cooperation between the authorities in the fields of inventory, follow up and preservation of freshwater pearl mussels as well as develop this area through concrete measures aimed at stopping the decline of the mussel population. The aim of the project is to: 1) Provide updated information about the reasons behind the decline of the mussel population as well as about the methods that aim at maintaining and restoring sterile populations. These methods can be used for preserving the mussel population within the whole EU. 2) Offer concrete information about the way to protect and restore the mussel population. This information will be presented in the final report of the project, in brochures drafted in several languages as well as during separate information sessions that would be organised within the framework of the project. The information that will be as comprehensive as possible, will be forwarded to state and local decision-makers as well as to both relevant public and private actors that deal with preservation of the mussel population or with relevant research, or to the institutions that through their mandate and activities can influence the state of the fluvial environment.