Endangered Species Law & Policy

On November 21, 2025, the U.S. Fish & Wildlife Service and National Marine Fisheries Service (collectively, the Services) published several proposed rules to revise their regulations implementing certain provisions of the Endangered Species Act (ESA). To a substantial extent, the Services are proposing to return to the regulations put in place by the first Trump administration in its prior rulemakings and thereby undo the changes put in place by the Biden administration in its prior rulemakings. This is the second in a series of blog posts that will briefly describe each proposed ...

On March 29, 2025, the U.S. District Court for the Western District of Texas (District Court) vacated the Endangered Species Act (ESA) special 4(d) rule for the northern distinct population segment (DPS) of the lesser prairie-chicken (LEPC). The 4(d) rule had prohibited, in most circumstances, “take” of the species’ northern DPS. Plaintiffs challenged the 4(d) rule in a number of ways, including on grounds that the U.S. Fish and Wildlife Service (Service) should have considered the economic impact of the 4(d) rule prior to its promulgation. As a result of the vacatur, it ...

On October 18, 2022, the U.S. Fish and Wildlife Service (Service) announced 12-month findings on a petition to list three California-based salamander species under the Endangered Species Act (ESA): the Kern Plateau salamander (Batrachoseps robustus), the Kern Canyon slender salamander (Batrachoseps simatus), and the relictual slender salamander (Batrachoseps relictus). All three salamander species occur in the southern Sierra Nevada Mountains in California. The Service determined that listing the Kern Canyon slender salamander and the relictual slender salamander is ...

This week, the U.S. Fish and Wildlife Service (“USFWS”) announced the availability of two revised economic analysis documents related to the agency’s proposed rule concerning incidental take under the Migratory Bird Treaty Act (“MBTA”).  The documents evaluate the potential for the proposed rule to impact small entities, including businesses, governmental jurisdictions, and other organizations.

When federal agencies issue a new proposed or final rule, they are required under the Regulatory Flexibility Act of 1980 (“RFA”) to evaluate the potential effects ...

On July 13, the U.S. Fish and Wildlife Service (Service) published a proposed rule to designate critical habitat for the pearl darter (Percina aurora) under the federal Endangered Species Act (ESA).  Listed as a threatened species under the ESA in September 2017, the pearl darter is a small, snub-nosed fish whose historical range includes Mississippi and Louisiana.  The proposed critical habitat designation for the pearl darter includes a total of approximately 517 river miles along the Pascagoula River and Pearl River basins, which run across multiple counties in ...

In 2012, the U.S. Fish and Wildlife Service (Service) published a final rule designating 1,724 acres as critical habitat for the endangered Riverside fairy shrimp (Streptocephalus woottoni).  Included in that designation were 56 acres of private land, on which the plaintiff, Otay Mesa Property, L.P. (Otay Mesa), had planned to build a recycling facility and landfill.  Because of the land use restrictions potentially implicated by the critical habitat designation, Otay Mesa challenged the final rule in federal court, asserting that (1) the Service improperly ...