Berg

We must decide the proper scope of intervention as of right pursuant to Federal Rule of Civil Procedure 24 (“Rule 24”) in the context of environmental litigation. Pardee Construction Company (“Pardee”) and four national and local building trade associations (the “Builders”) (collectively, “Applicants”) appeal the denial of their motion to intervene in an action for declaratory and injunctive relief brought by the Southwest Center for Biological Diversity and other environmental groups (collectively, “Southwest”) against various officers of the U.S. Fish and Wildlife Service (“FWS”), the Department of the Interior, and the City of San Diego (the “City”), and the U.S. Army Corps of Engineers (collectively, “Defendants”). Southwest challenges the measures Defendants have taken to ensure the protection of seven endangered wetland species, and th,e validity of conservation plans and an agreement and permit that regulate development projects affecting these and other protected species. We have jurisdiction over the denial of a motion to intervene as of right as a final appealable order pursuant to 28 U.S.C. § 1291 . Donnelly v. Glickman, 159 F.3d 405, 409 (9th Cir.1998). We reverse the…