Ecological Risk Screening Summary - Channeled Applesnail (Pomacea canaliculata) - 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.

Channeled Applesnail (Pomacea canaliculata) is a freshwater gastropod native to the Lower Paraná, Uruguay, and La Plata basins in Argentina, Paraguay, Uruguay and southern Brazil. It is sometimes used for aquaculture in Asia. It has been commonly confused with a congener, Pomacea maculata, that occurs in sympatry in the La Plata, but not the Amazon, basin, but recent molecular studies have determined that the two species are genetically distinct. P. canaliculata has been widely introduced and become established in eastern Asia, western North America, outside its native range in South America and, most recently, Africa. Reasons for introduction include aquaculture potential, aquarium dumping, and weed control in rice agriculture. However, P. canaliculata has been found to cause substantial damage to taro and rice crops themselves, as well as to negatively affect macrophyte communities in wetlands, alter zooplankton communities, and reduce water quality. For these reasons, the History of Invasiveness is High. The climate matching analysis for the contiguous United States indicates establishment concern for this species. The highest match was found in the Southwest, where P. canaliculata is already established, but high matches were also found in the Southeast. The Certainty of Assessment is High due to the abundance of information available on introductions and impacts. The Overall Risk Assessment Category is High.