States Challenge Rule Changes That Limit Habitat Protection

On September 9, 2026, a group of state attorneys general filed two federal lawsuits that challenge major revisions to rules implementing the Endangered Species Act. The filings name the U.S. Fish and Wildlife Service and the National Marine Fisheries Service and ask the U.S. District Court for the Northern District of California to set aside the new regulations. The lawsuits assert that the changes will strip essential habitat protections and hinder recovery for imperiled species.

At issue are three regulatory moves finalized this summer: the removal of the agency’s regulatory definition of 'harm,' a revision that ends the automatic 'blanket' protections for newly listed threatened species under Section 4(d), and a new critical-habitat process that allows consideration of economic burdens and third-party objections when excluding areas from designation. The Department of the Interior and the Services argued the revisions align regulations with statutory text and provide clear procedures for weighing impacts.

State attorneys general maintain that the policy changes will permit developers, fossil fuel firms and other commercial interests to undertake projects that alter or destroy vital habitat so long as they do not directly kill or injure listed animals. The complaints cite science that identifies habitat loss as a leading cause of species decline and say the new rules effectively prioritize economic concerns over biological needs.

The litigation was brought by a coalition led by Washington and California and joined by many other states and the District of Columbia. The plaintiffs ask the court to block the rules while legal challenges proceed. Court schedules and further briefs will determine how quickly a judge addresses claims that these regulatory changes exceed the agencies’ authority and contravene the conservation goals Congress set when it enacted the Endangered Species Act in 1973.