In a unanimous decision (with Justice Kavanaugh not participating), the Supreme Court on November 27, 2018, remanded a controversial Endangered Species Act (ESA) decision for further consideration by the Fifth Circuit Court of Appeals. Weyerhaeuser v. U.S. Fish and Wildlife Service (FWS) The Court held that “critical habitat” must be “habitat.”

The Court agreed that the ESA did not require that the designated area have members of the species living on it when the determination is made. It did not directly rule on the scope of the term “habitat,” leaving that for the lower court. However, its discussion implies, while not directly ruling, that the area must be able to support recovery of the endangered species without the need for improvements. It also concluded that decisions by the FWS on whether to exclude areas from critical habitat designation on economic grounds are subject to judicial review.

The case involved the dusky gopher frog, which currently lives in Mississippi in areas of longleaf pine forests, with ephemeral ponds. Most of that habitat has disappeared, endangering the species. Because the frogs are currently found only in a few areas of Mississippi, the FWS designated not only those areas, but also a 1500 acre area in Louisiana as critical habitat. The record shows the frogs do not now live on the Louisiana parcel and could not survive as a sustainable population, unless the forested area was modified. The courts below held that FWS acted within its discretion in designating areas that would require modification to support the species, and declined to review the FWS determination that the area should be excluded as critical habitat in balancing the costs and benefits.

On remand, it appears the question will not be bright line. At the Supreme Court, FWS conceded that critical habitat must be habitat, but argued that the frog could survive in the Louisiana habitat, although recovery of a sustainable population would require modification of some of the forest area. A distinction, but one the court of appeals may find less than compelling when it also considers whether the FWS was arbitrary in its decision to designate the area as critical despite the potential $33MM cost to the owners if the land cannot be developed.

It had been expected that the Supreme Court would place limitations on the exercise of discretion in the designation of critical habitat. It did, but did not go as far as some may have hoped. That is likely the price of obtaining a unanimous court.