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9th Circuit Says Endangered Species Critical Habitat Not Limited to Where the Species Resides - Agency May Restrict Analysis of Economic Costs of Critical Habitat


In Arizona Cattle Growers' Association, ___ F.3d ___, 2010 WL 222036 (9th Cir. June 4, 2010), the 9th Circuit Court of Appeals upheld a Fish and Wildlife Service ("FWS") determination under the Endangered Species Act ("ESA") that critical habitat for the threatened Mexican spotted owl is not limited to areas where the owl actually resides but can encompass any area the owl uses, including the birds' migratory pathway.  That standard means the thousands of miles of migratory bird flyways used by ESA listed birds could become protected critical habitat.  The decision also held, in stark disagreement with the 10th Circuit, that when implementing the ESA's requirement to decide whether the economic costs of designating an area as critical habitat outweigh the benefits, FWS can ignore economic costs caused by the critical habitat designation if such costs can also be attributed to listing the species.  The 10th Circuit in New Mexico Cattle Growers' Ass'n v. Fish and Wildlife Service, 248 F.3d 1277 (10th Cir. 2001), had ruled that allowing FWS to ignore the economic costs of critical habitat designations by attributing all such costs to the listing meant that economic issues would never be considered anywhere in the ESA because, unlike critical habitat designations, the ESA precludes weighing economic costs when listing a species.  Finally, the 9th Circuit stated the ESA's requirement that FWS use the best scientific data available in making decisions "does not require that the FWS act only when it can justify its decision with absolute confidence."

The 9th Circuit began by citing the statute that critical habitat includes areas essential for the species' conservation.  16 U.S.C. 1532(5)(A).  The court said the limits of critical habitat outside the area where the species resides are measured using two tests, frequency of use and uncertainty.  Frequency, said the court, considers whether the area is used intermittently for foraging, juvenile population dispersal, or migration.  Such areas can be critical habitat because "Congress clearly intended that [agencies] give the highest of priorities and the benefit of the doubt to preserving endangered species."  In short, the 9th Circuit decided that if an area "contains" a listed species for "any reasonable span of time" it can constitute critical habitat.  Given that vast land areas of the U.S. are part of the migratory bird flyways, the 9th Circuit's opinion paves the way for all of these areas to become critical habitat for listed species.  Reaching beyond even this broad principle, the court went on to find that because FWS presented evidence that there might be undiscovered owl sites, areas used by these undiscovered animals could also be included in critical habitat.

The 9th Circuit also reaffirmed its ruling in Gifford Pinchot Task Force v. Fish and Wildlife Service, 378 F.3d 1059 (9th Cir. 2004), that critical habitat is not limited to areas necessary for the species' survival but also includes areas necessary for the conservation, i.e., recovery, of the species. 

The only limitation the court placed on designating critical habitat is that an area whose only qualification is that it is suitable for future occupancy may not be included in critical habitat.  The area must be occupied, as broadly defined by the court.

As to the uncertainty factor in designating critical habitat, i.e., the data needed to support a decision, the court held FWS is not required to justify its decision "with absolute confidence" because the "ESA accepts agency decisions in the face of uncertainty."  Giving FWS vast discretion, the court said that "factual questions" of whether an area is used with sufficient frequency to be critical habitat "are within the purview of the agency's unique expertise."  This standard would apply to all agency decisions under the ESA. 

Finally, the court addressed the ESA provisions that FWS can exclude areas from critical habitat based on the economic burden of the designation.  In evaluating these economic costs, Arizona Cattle Growers, citing 10th Circuit precedent, had argued FWS must include all economic costs and cannot exclude economic burdens because they already exist due to the species listing.  The Cattle Growers argued that allowing FWS to exclude economic costs associated with listing meant FWS can attribute all economic costs to the listing and effectively never do an analysis of the economic effect of a critical habitat designation, as required by the ESA.  Not surprisingly, FWS took the opposite view.  The 9th Circuit sided with the agency.

A partner with Nossaman, George Mannina, Jr. has more than three decades of experience with environmental litigation and government relations.  He can be reached at 202.887.1491 or

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