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. This additional information will help inform decisions on where, when, and how the species may be used to minimize risks of them becoming invasive.
C. nasus is a fish species native to Eurasia and North America. Its distribution outside of its native range is not certain, and little information is available regarding impacts or potential impacts from introductions of this species. C. nasus has a medium climate match with the contiguous United States, with the areas of highest match located in the Northern and Great Plains states. More research is needed to fully understand the impacts, if any, from introductions of this species. Absence of this research makes the certainty of this assessment low. Overall risk assessment category is uncertain.