The Trump administration has issued a new interpretation of the Endangered Species Act (ESA) that exempts inadvertent harm to protected plants and animals from liability, marking a significant shift in federal enforcement of the landmark environmental law. Under guidance issued September 14 by Brian Nesvik, director of the U.S. Fish and Wildlife Service, only intentional acts targeting endangered species will now be considered illegal "takes" under the ESA.

This policy reversal signals a departure from the agency’s longstanding practice of holding individuals and companies responsible for unintentional harm to protected species such as grizzly bears, manatees, and spotted owls. Nesvik’s directive clarifies that incidental impacts—such as logging a tree where bats roost—do not constitute a violation unless the action is purposefully aimed at killing or capturing the animals. “Felling a tree is not a take of the bats roosting in it unless the tree is felled for the purpose of killing or capturing them,” the directive states.

The interpretation builds on a July rule from the Fish and Wildlife Service that narrowed the legal definition of “harm” under the ESA and draws on a dissenting opinion by former Supreme Court Justice Antonin Scalia from a 1995 case. Together, these measures reflect the administration’s broader effort, encouraged by Republican lawmakers and industry groups, to reduce regulatory burdens on businesses by limiting the scope of endangered species protections.

Supporters of the changes argue that the revision aligns enforcement with the original intent of the ESA and follows recent Supreme Court rulings that constrained federal agencies’ authority to interpret environmental statutes. The Interior Department, overseeing the Fish and Wildlife Service, emphasized in a statement that ESA prohibitions against activities such as harassing, pursuing, hunting, wounding, or killing protected species remain intact under the new guidance.

However, the shift has drawn criticism from environmental advocates and former agency officials who warn it will create significant loopholes. Dan Ashe, who previously led the Fish and Wildlife Service under President Barack Obama, characterized the move as a dramatic break from the law’s history, saying it “completely relieves people of any responsibility for their actions, even consequences that can be easily predicted.” Conservation groups and several states have responded by filing lawsuits in an effort to challenge and overturn the new policies.

Critics argue the revised interpretation could accelerate the decline of threatened species by permitting incidental deaths during activities such as timber harvesting or dam construction, undermining habitat protections that have been fundamental to species recovery efforts. They caution that the changes risk eroding decades of environmental progress by opening the door to habitat destruction and increased mortality among vulnerable animals and plants.