Hagerman Fossil Beds National Monument - Fish

The aquatic ecosystem is linked inextricably, through the riparian zone, with the terrestrial ecosystem. Species of fish in this stretch of the Snake River include rainbow trout ( Salmo gairdneri ), small-mouth bass ( Micropterus dolomieui ), chub ( Couesius plumbeus ), suckers ( Catostomus spp .), and non-native carp ( Cyprinus carpio ). Sturgeon ( Acipenser transmontanus ), although once plentiful, are now rare.

Much of the Snake River and many of its reaches were declared critical habitat for the Snake River sockeye salmon ( Oncorhynchus nerka ), a federally listed endangered species, and the Snake River fall Chinook salmon ( Oncorhynchus tschawytscha ), a federally listed threatened species. In addition, the entire Snake River Basin has been designated as an Evolutionary Significant Unit for the West Coast steelhead ( Oncorhynchus mykiss ).

Because the Monument lies adjacent to the Snake River, which is part of the tributary system of the Columbia River, the Bull Trout ( Salvelinus confluentus ) from the Columbia River population within the Columbia River Basin is also listed as threatened .