30 June 2025

American Signal Crayfish Discovered in Sverdlovsk Region

During the period from June 23 to 25, during in-kind hydrobiological studies at the Isetskoye Reservoir, specialists from the Ural branch of the Russian State Research Center of Fisheries and Oceanography (VNIRO) for the first time in the Middle Urals identified a large stable population of the American signal crayfish (Pacifastacus leniusculus) in the warm water discharge zone of the Sredneuralskaya GRES.

This species, which lives in the western part of North America, has spread widely in Europe as an invasive alien species. In Russia, the species is registered in the Kaliningrad region and was discovered in the Leningrad region in 2024.

Its distinctive features are a smooth and slippery shell surface, rounded claws with a light spot in the fork and a bright orange lower surface.

The branch specialists examined more than 20 specimens caught by amateur fishermen. Their sizes with claws ranged from 13 to 17 cm, which indicates successful acclimatization of the accidentally populated species and its possible further spread in the Sverdlovsk region.

Press service of VNIRO

сигнального рака

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