Rahway River migrations. Fish ladders are inundated structures with small underwater steps that allow fish to navigate around a dam and continue their migration. Other approaches include removing obstructions that are inoperative or no longer serve their purpose, or improving water quality and reducing debris that obstructs passage. The fish targeted for upstream passage at the Rahway River Water Supply Dam are alewife (Alosa pseudoharengus), blueback herring (Alosa aestivalis), gizzard shad (Dorosoma cepedianum), white perch (Morone Americana) and the endangered American eel (Anguilla rostrate). Alewife and blueback herring are collectively referred to as river herring due to their similarity in appearance, range,
Alosa agone Alosa agone Alosa agone is a species of ray-finned fish in the genus "Alosa". "Alosa agone" is an endangered species of the "Alosa" genus. "Alosa agone" are common in the Mediterranean and the western Balkans. There are also landlocked populations found in Italy. The distribution of reproductive communities and the conservation status of Alosa agone in the central and eastern parts of the Mediterranean areas are poorly known. Alosa agone’s numbers have declined due to barriers such as dams in their local areas. These barriers prevent them from getting upstream to their spawning grounds and reproducing. Improved water quality in