Combining storm flood water level and topography to prioritize inter-basin transfer of non-native aquatic species in the United States

Flooded areas can create temporary connections between adjacent drainages and are a relatively understudied pathway for the spread of aquatic invasive species. The Nonindigenous Aquatic Species Database’s Flood and Storm Tracker maps were developed to help natural resource managers with post-storm aquatic invasive species detection and assessment efforts. As of the summer of 2023, 16 Flood and Storm Tracker maps have been published from hurricanes and flooding events in the United States and territorial islands. Three regions along the coasts of the Gulf of Mexico and Atlantic Ocean had overlapping areas of repeated flood impacts, and fifteen pairs of adjacent river basins were potentially connected during floods. Each map had a median of 77 non-native freshwater taxa and a median of 3 U.S. prohibited species within their respective flood-impacted area. The Flood and Storm Tracker maps provide resource managers with information about new aquatic invasions due to potential flood dispersal that can assist with early detection and rapid response systems.