Anadromous Fish

Fish Run

Anadromous Fish Run (.jpg - 58k)

Anadromous Fish are fish that hatch in freshwater, spend their adult lives in saltwater, and return to freshwater to spawn. The fish migrate by fish runs, streams connecting bodies of marine and freshwater. The most significant native species of anadromous fish on Cape Cod are alewives (Alosa pseudobarengus), blueback herring (Alosa aestivalis), and white perch (Morone americana).

Anadromous fish generally return to spawn by the same route that they followed to the ocean as juveniles, and they return to the same location in which they hatched. Anadromous fish are important links in both marine and freshwater food webs, and they are an important renewable resource to humans. They are recreationally, aesthetically, and commercially important.

Overfishing of anadromous fish is a concern, as are human activities that pollute, obstruct, or otherwise alter the runs.