Species that are considered uncertain risk need a more in-depth assessment beyond the Risk Summary to better define the species’ risk to U.S. environments.
Acipenser gueldenstaedtii, the Russian Sturgeon, is a sturgeon native to the Black, Azov, and Caspian Sea basins, although it has been extirpated from much of its native range. It has been deliberately introduced widely in Europe because of its value in caviar production. A. gueldenstaedtii has a high climate match with freshwater environments in the contiguous United States. Climate match to marine environments cannot be assessed with the climate matching analysis employed here. Despite multiple documented introductions of this species outside of its native range, no information is available on any negative impacts from this species. Certainty of this assessment is therefore low because further information is needed to adequately assess the risk this species poses to the United States. The overall risk assessment category is Uncertain.