STATUS OF FRESH-WATER FISHES OF THE UNITED-STATES - OVERVIEW OF AN IMPERILED FAUNA

Conservation biologists have begun a concerted effort to educate the p ublic, resource administrators, and politicians about the decline of t emperate ecosystems, including their fishes. The United States harbors the most diverse temperate freshwater fish fauna in the world with ab out 790 species represented, about 90% of which are nongame fishes. Fr om a state-by-state perspective, diversity of fishes in the United Sta tes is concentrated in the South, primarily in Alabama, Kentucky, Geor gia, Mississippi, Tennessee, and Virginia, each of which supports at l east 200 native fish species. Endemicity of fishes ig high in both the South and West; in the latter region, up to 70% of fishes in some dra inages (e.g., Colorado River) are endemic. Imperilment apparently is n ot confined to particular taxonomic groups. Of the five most diverse f ish families in the United States, total imperilment ranges from 7% in the Centrarchidae to 50% in nonanadromous salmonids and indicates wid espread and pervasive degradation of aquatic habitats. Imperilment is most acute in areas of high diversity and/or endemicity (i.e., the sou thern and western states). States with 20 or more imperiled fishes inc lude Alabama, Arizona, California, Georgia, Nevada, New Mexico, North Carolina, Oregon, Virginia, Tennessee, and Texas. Backlogs in listing species as federally threatened or endangered are most egregious (10 o r more backlogged taxa) in Alabama, Georgia, Nevada, and Tennessee.