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,
Araucanian herring Araucanian herring The Araucanian herring, "Clupea bentincki", is a fish species in the genus "Clupea" of the family Clupeidae. It is an epipelagic fish, silvery below and dark blue above, which schools in coastal waters off the west coast of South America. There it filter feeds on smaller plankton such as diatoms. It reaches sexual maturity when it is about 10 centimetres long, and is a pelagic spawner, spawning between June and November. The Araucanian herring is a commercial species, largely used for fishmeal. Based on the FAO fishery statistics, it was the 12th most important capture fish species in