Ecological Risk Screening Summary - Feathered Mosquitofern (Azolla pinnata) - 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.

Azolla pinnata, Mosquito Fern, is a freshwater aquatic plant that is native to Africa and Madagascar, India, Southeast Asia, China, Japan, Oceania, and Australia. Azolla species in general, and A. pinnata in particular, are used in farming as a green fertilizer, in aquariums, as animal feed, in traditional medicines, and as population control for mosquitos. A. pinnata has been introduced and become established in Florida, Brazil, New Zealand, the Cook Islands, and Singapore. It has been introduced but the status is currently unknown in Arizona, Louisiana, the Marshall Islands, and western Europe. The History of Invasiveness for Azolla pinnata is classified as High. Adverse impacts were reported, such as choking and displacing native aquatic vegetation, altering habitat for wildlife, reducing water quality, and disrupting water access. The climate matching analysis for the contiguous United States indicates establishment concern for this species. The climate match was high along the southern Atlantic and Gulf Coasts, as well as southern to central Texas extending to the Midwest. The Certainty of Assessment is Low due to the uncertainty in the distribution and the limited amount of scientifically defensible impact information. The Overall Risk Assessment Category is High.