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.
Rhodeus ocellatus, the Rosy Bitterling, is native to mainland China, Taiwan, Japan and possibly Russia. It has been introduced to Fiji, where it is established, and Central Asia, where its status is unknown. Introductions have been unintentionally through transfer of other aquatic organisms for aquaculture or intentionally through release of aquarium pets. Rhodeus ocellatus is reported to be a pest at fish farms where it preys on eggs and juveniles of commercial species and competes with them for food, but further research is needed on the extent and significance of such impacts. There is more scientific support for impacts of R. ocellatus ocellatus on R. ocellatus kurumeus, but impacts at the subspecies level are not considered in assessing history of invasiveness in this risk screen. History of invasiveness is classified as Data Deficient. R. ocellatus is also susceptible to epizootic ulcerative syndrome, an OIE-reportable disease. The climate match with the contiguous United States is high, especially in the Southeast. The certainty of assessment was low due to questions about the extent of the native range and the lack of detailed and scientifically credible information on impacts of introduction. The overall risk assessment category for Rhodeus ocellatus in the contiguous United States is Uncertain.
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Uncertain Risk
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