Turkey has a rich variety of fish species in the rivers with a total length of 177,714 km in Turkey. Freshwater fish live in rivers, streams, creeks, dam lakes, natural lakes, wetland areas, etc.
The life of migratory fish is threatened by the anthropogenic impact on aquatic habitats. Human activities that disrupt river integrity can be listed as; dam and hydro power plant constructions, high levees, sluices, weirs and bridges, sand-gravel quarries, recreational works, wetland depletion, water pollutions, overfishing, habitat losses, climate changes, water pumping from a river to other river basins, drinking water, dried river beds etc. The most important diadromous fish species in Turkey are sturgeon species (Acipenseridae), European eel (Anguilla anguilla) and Black Sea trout (Salmo trutta labrax). In this study, the past and present status of these species are reviewed.