Diadromous fish are a species group that includes both anadromous and catadromous fish. Anadromous fish, such as the American Shad, Alewife, or Blueback Herring, live most of their lives in salt water but are born in fresh water and return to fresh water to spawn ¹. Catadromous fish, such as eels including the American Eel, display the opposite life history - spending their adult life in freshwater and migrating into the ocean to spawn ¹. Diadromous fish are essential to maintaining ecosystem connectivity; they provide important ecosystem services by transporting energy and marine-derived nutrients between freshwater and ocean environments ². Diadromous fish are iconic to the New England region and were an important resource to early American colonization. These fishes have experienced wide-spread and systematic declines since the industrial revolution due to a range of human stressors including pollution, overfishing, and habitat loss (e.g. dams) ³.