UNITED STATES COURT OF APPEALS FOR THE NINTH CIRCUIT CENTER FOR BIOLOGICAL No. 20-15654 DIVERSITY, D.C. Nos. Plaintiff-Appellee, 4:17-cv-00475- v. JAS 4:17-cv-00576- UNITED STATES FISH AND JAS WILDLIFE SERVICE, 4:18-cv-00189- JAS Defendant-Appellee, OPINION v. ROSEMONT COPPER COMPANY,

Intervenor-Defendant- Appellant.

Appeal from the United States District Court for the District of Arizona James Alan Soto, District Judge, Presiding

Argued and Submitted September 23, 2022 Pasadena, California

Filed May 17, 2023 2 CTR. FOR BIOLOGICAL DIVERSITY V. USFWS

Before: Sandra S. Ikuta, Danielle J. Forrest, and Holly A. Thomas, Circuit Judges.

Opinion by Judge Forrest; Partial Concurrence and Partial Dissent by Judge H.A. Thomas

SUMMARY *

Environmental Law

In a case in which intervenor Rosemont Copper Company challenges the U.S. Fish and Wildlife Services’s (FWS) designation of certain areas in southern Arizona as critical habitat for jaguar under the Endangered Species Act (ESA), the panel affirmed the district court’s vacatur of the FWS’s designation of the challenged area as occupied critical habitat; reversed the district court’s grant of summary judgment in favor of the FWS regarding its designation of that same area and of Subunit 4b as unoccupied critical habitat; vacated the grant of summary judgment in favor of the Center for Biological Diversity (Center); and remanded with directions that the case be returned to the agency for further proceedings. This litigation was initiated by the Center after the FWS concluded that Rosemont’s proposed mine project would not destroy or adversely modify the designated critical habitat. Rosemont intervened and filed crossclaims against * This summary constitutes no part of the opinion of the court. It has been prepared by court staff for the convenience of the reader. CTR. FOR BIOLOGICAL DIVERSITY V. USFWS 3

the FWS, arguing that certain of its critical-habitat designations for the jaguar violated the Administrative Procedures Act (APA) and the ESA. This case concerns only Unit 3, which covers 351,501 acres and spans several counties and mountain ranges, including the Santa Rita Mountains; and Subunit 4b, which covers 12,710 acres and is a corridor connecting the Whetstone Mountains and the Santa Rita Mountains. The FWS argued that the district court erred in rejecting the FWS’s designation of Unit 3 as occupied critical habitat, and Rosewood argued that the district court erred in upholding the FWS’s designation of Unit 3 and Subunit 4b as unoccupied critical habitat because the standard the FWS used was something less demanding than essential for the conservation of species. First, the panel held that the only plausible construction of “essential” in the ESA’s definition of “critical habitat” is area that is indispensable or necessary to conservation, not merely beneficial to such efforts. Second, the panel considered whether the FWS’s critical habitat designations of Unit 3 and Subunit 4b were proper. Because the FWS designated the northern Santa Rita Mountains as occupied critical habitat based on irrelevant photographs from decades after the jaguar was listed as endangered and a single timely sighting from a different mountain range, the panel affirmed the district court’s conclusion that the FWS’s challenged occupied critical- habitat designation was arbitrary and capricious. Next, the panel addressed Rosemont’s argument tha