A Summary of Recent Downstream Passage Results for American Eel in the North Atlantic-Appalachian Region; where do we go from here?

Sojkowski, Bryan¹, Julianne Rosset², Jessica Pica¹, ¹USFWS R5 Regional Office, Hadley, MA, ²USFWS Maine Field Office, East Orland, ME

American eel (Anguilla rostrata), a catadromous species, are mysterious creatures, capable of reaching habitat in upper watersheds even when anthropogenic barriers stand in their way, moving throughout Rivers under the cloak of darkness, and spawning in the Sargasso Sea undetected. American eel will grow to an impressive size in freshwater over a period of up to 20 years prior to making their journey back to the sea. However, this means they need to attempt to navigate past multiple hydroelectric dams to complete their life cycle, which leads to many of these precious creatures being injured or killed and has resulted in declines in their historical population sizes. While standard radio and acoustic telemetry methods have been utilized to measure the impact of hydroelectric dams on fish passage, it is difficult to lean on these results because of the highly variable movement rates of eels that are alive, injured, or dead. The intent of this presentation is to highlight the unknowns when assessing the results of downstream American eel fish passage studies, even when survival rates seem to be high. A discussion of recent study results within the United States Fish and Wildlife’s North Atlantic-Appalachian Region will be provided as well as how these results raise questions about other priority species within the Northeast.