Ecological Risk Screening Summary - Buffalo Pebblesnail (Gillia altilis) - 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.

Gillia altilis, the Buffalo Pebblesnail, is a freshwater snail that is native to Atlantic Coastal drainages in North America from Vermont to South Carolina. This species of snail is usually found in freshwater stream environments in areas with silty substrates, stagnant waters in lakes and streams, as well as rapidly moving waters. G. altilis has been introduced to the Great Lakes region through means of the Erie Canal. G. altilis is considered established in Lake Ontario and the Erie Canal, however, no information on impacts of its introduction was found. The History of Invasiveness for Gillia altilis is classified as Data Deficient due to lack of information regarding impacts of introduction or trade information. The climate matching analysis for the contiguous United States indicates establishment concern for this species outside of its native range. Areas of high match were generally found from the central United States to the East Coast. Areas of low and medium match were found in the Great Plains and westward. The Certainty of Assessment for this ERSS is classified as Low due to lack of information on impacts of its introduction. The Overall Risk Assessment Category for Gillia altilis in the contiguous United States is Uncertain.