On March 28, 2019, a federal judge overturned the U.S. Fish and Wildlife Service’s (“USFWS”) rejection of a petition to delist an endangered karst invertebrate species, the Bone Cave harvestman (Texella reyeisi) (“BCH”), which is known to occur only in central Texas.

American Stewards of Liberty and others (“Plaintiffs”) had claimed that USFWS’ rejection of a 2014 petition to delist the BCH was arbitrary and capricious because, among other things, USFWS based its rejection on the petition’s supposed failure to provide BCH population trend data that was unavailable and is, potentially, unattainable. As noted in the petition, the best available population data for BCH is the evidence of its presence in separate caves or cave clusters. Since the BCH’s listing in 1988, the number of caves in which the species is known to occur has grown from half a dozen caves to more than 200—an increase of more than 3,000 percent.

The court held that USFWS’ requirement for population trend data violated the Administrative Procedure Act and remanded the decision back to USFWS, for a new 90-day finding. In its ruling, the court noted that Plaintiffs’ most compelling argument was that USFWS had “required a higher quantum of evidence than is permissible under the Endangered Species Act and implementing regulations governing” 90-day findings.  Specifically, the court held that regulations governing USFWS’ review of petitions to list and delist species require a petition present information which is, in fact, available, and that USFWS committed “a clear error in judgment” when the agency called for more evidence than is required under the law. Pursuant to the ruling, USFWS must undertake a fresh review of the 2014 petition and must use available species population information, as opposed to population information USFWS “admits is impossible to attain.”  Nossaman attorneys Paul Weiland, Alan Glen, Rebecca Barho, and Brooke Wahlberg represented Plaintiffs.

The court simultaneously rejected the contention of plaintiff-intervenors, who argued that USFWS’ regulation of the BCH violated the Necessary and Proper Clause and Commerce Clause, and the Tenth Amendment to the Constitution. Other parties participated in various capacities in the litigation, including the Center for Biological Diversity, Travis Audubon,  Defenders of Wildlife, Mountain States Legal Foundation, the State of Texas, and Williamson County, Texas.