Delta smelt on the verge: Efforts to save smelt have far-reaching impact
Two factors are believed to weigh heavily on the Delta smelt’s fate. The biggest is the reduction in fresh water in the Delta since water started flowing southward via the California Aqueduct in the 1960s. … The other threat to Delta smelt are larger fish particularly non-native striped bass and largemouth bass that were introduced to the Delta by man.