The Trump administration proposes to exclude habitat modification as a potential violation of the Endangered Species Act, eliminating an Interior Department regulation in place since 1975.

The ESA prohibits harming endangered and threatened species. The Interior Department has long defined “harm” to mean habitat changes that jeopardize populations of protected species.

The U.S. Fish and Wildlife Service and National Marine Fisheries Service announced April 17 in the Federal Register they plan to repeal the definition and let the word “harm” speak for itself.

The definition of “harm” went beyond the law and is no longer defensible because the U.S. Supreme Court struck down the Chevron deference, according to the agencies.

The Chevron deference allowed agencies to adopt “reasonable” regulations, even if they were not expressly authorized by law or were not necessarily the “best” interpretation of the law. “We are undertaking this change to adhere to the single, best meaning of the ESA,” the agencies stated.

The ESA definition of “harm” has been a prime way to protect habitat, Center for Biological Diversity endangered species coordinator Noah Greenwald said.

“It’s a big deal, for sure,” he said. “I think you’ll see a lot more species go extinct. You can’t protect species without protecting the places they live.”

The ESA prohibits “take” of a protected species. The law elaborates that “take” means harass, harm, pursue, hunt, shoot, wound, kill, trap, capture or collect. While the other words needed no elaboration, the Interior Department defined “harm” to mean habitat modification.

Oregon timber companies, landowners and families dependent on the forest-products industry challenged the definition in the 1990s. They claimed the definition of harm as applied to the red-cockaded woodpecker and northern spotted owl harmed them economically.

In a 6-3 decision, the Supreme Court in 1995 upheld the definition in Babbit v. Sweet Home Chapter of Communities for a Great Oregon.

The majority ruled the definition reasonably interpreted Congress’ desire to protect species. The ruling cited the Chevron deference.

The Supreme Court eliminated the Chevron deference in June in the Loper Bright ruling. Federal agencies are now obligated to find the “best” interpretation of a law, not just a reasonable one, according to the Fish and Wildlife Service and National Marine Fisheries Service.

“We have concluded that our existing regulations, which still contain the definition of ‘harm’ contested in Sweet Home, do not match the single, best meaning of the statute,” the agencies stated.

Instead, the agencies propose to embrace the reasoning of the late Supreme Court justice Antonin Scalia, who dissented in the Sweet Home ruling.

Scalia said human ingenuity could find all sorts of ways to harm an animal, like cutting a tree to get a bird or draining a pond to get one turtle.

But using the ESA to regulate habitat on private land to preserve entire populations subjects farmers to financial ruin and converts farmland to “national zoological use,” Scalia wrote. Congress couldn’t have intended that, he wrote.

The federal agencies said the rule change would apply going forward and not change the terms of already issued permits. The agencies will take public comments on the proposal until May 19.