Table 1. Drivers of diadromous fish decline by geographic area, major taxa of concern, and potential for remediation.

Driver	Geographic area	Representative taxa of concern	Status
Overfishing	U.S. coastal waters and coastal rivers	Striped bass, Pacific salmonids	Broadly regional, somewhat remediated
Pollution	Urban and industrialized rivers and ports	American shad, Atlantic sturgeon	Localized to watersheds, often remediated, but with exceptions including legacy pollutants
Non-native species	U.S. coastal rivers	Alosines, salmonids	Broadly regional and largely irreversible
Climate change	U.S. coastal waters and coastal rivers	All taxa	Reversible in theory but not short-term
Habitat degradation	U.S. coastal waters and coastal rivers	All taxa	Highly localized and varyingly reversible
Agricultural water withdrawals	California; eastern Oregon and Washington	Delta smelt, Pacific salmonids	Regional, dependent on climate, precipitation, water rights
Hatcheries	Northeast and Northwest United States	Salmonids	Localized and species specific, easily eliminated except in cases of proven value
Aquaculture	Northeast and Northwest United States	Salmonids	Localized to regional, due to escapees, species specific
Mortality from hydro-electric facilities	Atlantic, Gulf of Mexico, and Pacific coast rivers	Primarily American eel	Highly localized but widespread; little remediation occurring
Reduced connectivity from damming	U.S. coastal rivers	All taxa	Highly localized and available for remediation