How have dams affected beluga sturgeon in the Volga River?

The construction of dams and reservoirs along the Volga River has significantly harmed the beluga sturgeon by blocking or severely curtailing its access to essential spawning grounds.1

As an anadromous species, the beluga sturgeon typically lives in the Caspian Sea but must migrate into the Volga and other inflowing rivers to reproduce. The dam system has fundamentally altered the river's habitat, which, combined with industrial, municipal, and agricultural pollution, has led to a major deterioration of the river's fisheries. Due to these disruptions, approximately three-fifths of the Caspian sturgeon population are now bred artificially to compensate for the loss of natural spawning environments.1