Ecological Risk Screening Summary - European Bullhead (Cottus gobio) - Uncertain Risk

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.

The history of invasiveness for Cottus gobio is not documented. One record of introduction into Norway was found but some authors (Frilund et al. 2009) state that it is more likely a natural range expansion instead of a non-native introduction. There were some records of invasive hybridized sculpins, but it was not clear where they were invading and which species were producing the hybrids. The climate match was high, particularly in the Great Lakes and areas of the Great Plains. The certainty of assessment is medium. The overall risk assessment category is uncertain.