The Ninth Circuit Court of Appeals has upheld the U.S. Fish and Wildlife Service’s (FWS) designation of 850,000 acres of critical habitat for 15 federally protected vernal pool species under the Endangered Species Act (ESA), rejecting a challenge by building industry groups. Home Builders Ass’n of N. Cal. v. FWS, No. 07-16732 (9th Cir. 8/9/10). Vernal pools are a “unique kind of wetland ecosystem” that exists temporarily following fall and winter rains. The pools are home to a diverse group of species including freshwater crustaceans, amphibians, insects, and plants.  

Plaintiffs challenged the designation on the following technical grounds: (i) FWS erred in designating as critical habitat those areas in which the physical or biological features essential to the conservation of a species do not occur simultaneously; (ii) FWS failed to determine when the protected species will be conserved; (iii) FWS erred in discussing occupied and unoccupied habitat designations together; (iv) FWS erred in designating as critical habitat areas that contained no “primary constituent elements” (PCEs) by including buildings, paved areas and boat ramps; and (v) FWS failed to properly account for the economic impact of its critical habitat designation. The district court rejected plaintiffs’ arguments, and plaintiffs appealed, again raising the five technical challenges.  

Rejecting plaintiffs’ arguments, the appellate court ruled that (i) the ESA does not require that two elements essential for the conservation of a species need be present in the same area at the same time; (ii) the ESA does not require that FWS determine exactly when conservation will be complete; (iii) under the ESA, an area constitutes “critical habitat” if it meets the requirements for occupied habitat or for unoccupied habitat, 16 U.S.C. § 1532(5)(A); (iv) the statute does not require that FWS separate buildings, paved areas and boat ramps from the critical habitat designation; and (v) the FWS did not fail to properly account for the economic impact of its designation.