Alosa kessleri, also referred to as the Caspian anadromous shad, the blackback, or the black-spined herring, is a species of clupeid fish. It is one of the several species of shad endemic to the Caspian Sea basin.This is an anadromous species which ascends from the Caspian to the Volga river up to the Volgograd to spawn. Before the construction of th Volgograd dam it migrated up to the Kama and Oka tributaries.