Otay Mesa Property L.P., et al. v. US Dept. of the Interior, et al.

This case concerned the San Diego fairy shrimp, an aquatic animal found in southern California, that was designated as an endangered species under the Endangered Species Act of 1973, 16 U.S.C. 1533. Plaintiffs, companies that owned land along the California-Mexico border, sued to challenge the designation of 143 acres of their property as critical habitat for the San Diego fairy shrimp. The court held that because the Fish and Wildlife Services had not reasonably explained how one isolated observation, involving a single 2001 sighting of four ant-sized San Diego fairy shrimp on the property at issue, demonstrated that plaintiffs' property was "occupied" by the San Diego fairy shrimp in 1997 (the relevant statutory date), the court reversed the judgment of the district court and remanded. On remand, the court ordered the district court to vacate the designation of plaintiffs' property as critical habitat for the San Diego fairy shrimp.