The case centers on the dusky gopher frog, which Fish and Wildlife designated in 2001 as endangered, and whether the agency went too far in declaring a 1,544-acre tract in Louisiana “critical habitat” for the frog, even though it hasn’t been seen on that site since 1965.

Fish and Wildlife said that the parcel has attributes of a place for the animal to live, such as ephemeral ponds, is essential to the survival of the species and should be designated critical habitat. The agency noted that the site would need to be modified to have an open canopy of trees, something the frogs require.

Weyerhaeuser and other owners of the land, who planned commercial and residential development on the tract, challenged the Fish and Wildlife decision.

A federal district court in 2014 ruled in favor of Fish and Wildlife. In 2016, the U.S.  Court of Appeals for the Fifth Circuit upheld the district court’s decision, and the landowners then appealed to the Supreme Court.

'Habitat' not defined

Writing for the high court, Chief Justice John Roberts said the appellate court didn't clear up what the term "habitat" means. Roberts wrote that while the Endangered Species Act defines "critical," it doesn't define "habitat." 

He wrote, "Only the 'habitat' of the endangered species is eligible for designation as critical habitat." He said that the appellate court "concluded that 'critical habitat' designations under the statute were not limited to areas that qualified as habitat."

In remanding the case, the high court also said that the appellate court should consider whether Fish and Wildlife’s cost and benefit assessment of designating the Louisiana parcel as critical habitat was “flawed” in a manner that made the decision “arbitrary, capricious or an abuse of discretion.”

Tom Ward, National Association of Home Builders vice president of legal advocacy, said via email that the Supreme Court's decision "will have a positive impact for any landowner whose property is designated as endangered species 'critical habitat.' "

Ward pointed to language in the opinion that would direct federal agencies to first determine whether an area is a habitat for a species before  it can be deemed critical habitat. He also cited the section dealing with costs and benefits of a habitat designation.

Ward added, "As the [Supreme] Court noted, it is important to have judicial review of such government decisions because without it 'legal lapses and violatins occur.' "

NAHB filed briefs in the case before the high court and the appellate court. The group says Weyerhaeuser and another of the Louisiana tract's landowners are association members.

Nick Goldstein, American Road & Transportation Builders Association vice president of regulatory and legal issues, says, “What constitutes critical habitat for a species is something that is very important to the construction industry, because when an area is designated as critical habitat, that severely limits what can and can’t be done with that land.”

Goldstein says of the high court’s decision to remand the case, “I think you can say that that’s good for the industry.” But he adds, “This wasn’t a huge blow to the Endangered Species Act," because the matter was sent back for further action.

Environmentalists' reactions

One environmental group viewed the high court’s ruling as a narrow one. “While we’re disappointed, the ruling doesn’t weaken the mandate to protect habitat for endangered wildlife,” Collette Adkins, an attorney for the Center for Biological Diversity, said in a statement.

She added, "The dusky gopher frog's habitat protections remain in place for now, and we're hopeful the Fifth Circuit will recognize the importance of protecting and restoring habitats for endangered wildlife."

The center filed briefs in the case and years earler, had filed a lawsuit seeking to have the dusky gopher frog designated as endangered.

But another advocacy group, the Natural Resources Defense Council, had a more negative reaction to the ruling. Rebecca Riley, legal director for NRDC's nature program, said via email, "If endangered species are going to survive, we need to restore their habitat. The Supreme Court just made that much harder to do."

Justice Brett Kavanaugh didn’t vote on the Weyerhaeuser case. He had not been confirmed to a seat on the high court until after the justices had heard oral arguments in the matter.

Story updated on 11/28/18 with comments from National Association of Home Builders and 11/29/18 with comment from Natural Resources Defense Council.