Red List reports
There are multiple sources of threats to freshwater molluscs in Europe. In the majority of cases there is no single source of threats to each species, but usually a series of threats combined that lead to declining populations. In general, most threatened species are suffering as a consequence of declining water quality in freshwater rivers and lakes, which is a problem throughout Europe, mainly due to intensification of agriculture (affecting 36% of the species) and urbanisation (poor sewage control, impacting 29% of the species). The other major threat comes from the over-utilization of water which impacts 33% of freshwater species. By contrast, although invasive species are present, and have had an impact on some species, in general it is not a significant factor and impacts less than 5% of the threatened species. The major threats for the future are the increased frequency and intensity of droughts. Springs are already seeing declines in recharge during summer drought events.