Ecological Risk Screening Summary - Fishhook Waterflea (Cercopagis pengoi) - High Risk

Species that are considered high risk have a well-documented history of invasiveness in at least one location globally, and a high or medium climate match to the contiguous United States.

Cercopagis pengoi is a cladoceran native to the Black, Caspian, Azov, and Aral Seas. Beginning in the 1990s, C. pengoi was introduced and spread in the Baltic Sea and then in the Great Lakes of North America. At present, C. pengoi has established populations in all of the Great Lakes except Lake Superior, as well as New York’s Finger Lakes. Ballast water and fouled fishing gear are the predominant vectors for C. pengoi introduction and spread. Introduced populations of C. pengoi have been repeatedly associated with declines in native zooplankton and planktivorous fish, sometimes changing community trophic structure, although zooplanktivorous fish may be able to exploit C. pengoi as a food resource. Additionally, biofouling of fishing gear by C. pengoi can result in considerable economic costs. The climate matching analysis showed medium to high matches across much of the contiguous U.S. Overall risk posed by C. pengoi is high.