BOISE, Idaho (AP) — The Trump administration is violating the Endangered Species Act by expanding hunting and fishing by 3,600 square miles (9,300 square kilometers) on the national wildlife refuge system and national fish hatchery system, an environmental group says.

The Center for Biological Diversity on Tuesday filed a notice of its intent to sue the U.S. Fish and Wildlife Service, which manages the nation’s 550 national wildlife refuges. The formal notice is a precursor to a lawsuit, giving the agency 60 days to respond.

Interior Secretary David L. Bernhardt announced the expansion in August, saying it increases public hunting to 430 refuges and those open to fishing to 360.

“We're going to court to ensure that our nation's wildlife refuges can actually provide refuges for wildlife," said Collette Adkins, the center's carnivore conservation director. ”We've never before seen such a massive expansion of bad hunting practices on these public lands."

The U.S. Department of Justice defends government entities in lawsuits. Danielle Nichols, a spokeswoman, said the agency had no comment.

President Theodore Roosevelt founded the National Wildlife Refuge system in 1903, signing an executive order to establish the Pelican Island National Wildlife Refuge in Florida to protect several types of birds from ornamental plume hunters.

The expansion of hunting and fishing on the refuges this year followed a similar move in 2019 when the Trump administration expanded hunting and fishing on 2,200 square miles (5,700 square kilometers) of refuges in 37 states, much of which is considered critical habitat for waterfowl and other birds to rest and refuel during their migration.

Conservation groups have expressed concern that state and federal officials don’t appear to have a monitoring system to see what effect the changes might have.

But hunting groups generally welcomed the expansion, saying it would draw more people to the outdoors.