Conservation groups have petitioned the National Marine Fisheries Service (NMFS) to redefine hatchery-bred salmon and naturally spawned salmon as separate subspecies under the Endangered Species Act (ESA). The move is seen as an effort to insulate the ESA listing of 14 West Coast salmon runs from last year’s ruling by U.S. District Judge Michael Hogan invalidating NMFS’s listing of coastal coho under the ESA.

Hogan found that wild and hatchery salmon are indistinguishable and that NMFS has “arbitrarily and capriciously” distinguished between wild and hatchery fish in its listing of the coho. Environmentalists have also appealed Hogan’s ruling to the 9th Circuit Court of Appeals.