The lights will go out at the Interior Department unless a short-term funding extension is hammered out before the end of Dec. 21.

If that happens, the National Park Service will immediately stop providing visitor services, including restrooms, trash collection, and road and facilities maintenance, according to its January 2018 contingency plan. Preventative wildfire projects, such as prescribed burns, will also be called off, raising the possibility of more frequent and intense fires in the future.

The agency will only retain 3,298 of its 24,681 employees, according to its plan.

Further, because the parks remain open but aren’t patrolled, animals could potentially be vulnerable to poaching and off-season hunting. The Fish and Wildlife Service, which protects endangered species, plans on furloughing all but 1,331 of its 8,359 employees.

A shutdown of the Park Service could also have economic impacts on local communities and local businesses that rely on a steady stream of tourists, said Michael Reinemer, deputy director of communications strategy at The Wilderness Society.

The outdoor recreation economy accounts for $887 billion in annual consumer spending and is responsible for 7.6 million jobs, according to the Outdoor Industry Association.

But the Park Service can also be a useful lever for lawmakers who want to reopen the government because it’s such a vivid symbol of what a shutdown means in the real world, Jonathan Asher, government relations manager for conservation funding at The Wilderness Society, told Bloomberg Environment.

“What the Trump administration is trying to avoid are the visuals that happened in the 1990s, when people pulled up to Yellowstone Park and there were big ‘closed’ signs,” Asher said. “That’s bad publicity for the administration. The national parks hold a very special place in Americans’ minds and daily lives, because it’s one of the places where they interact on a very personal level with the federal government.”

Impacts on Mine Cleanup

Coal mine cleanup programs would also be affected. The Office of Surface Mining Reclamation and Enforcement would shrink down from 421 employees to a mere eight, according to its January 2018 contingency plan.

The office would retain its emergency program to respond to critical events such as landslides near homes and across roads, land subsidence beneath houses and public buildings, mine and coal waste fires, and open shafts.

The National Mining Association and American Petroleum Institute didn’t immediately respond to Bloomberg Environment’s request for comment.

Ongoing abandoned mine land reclamation projects are mostly issued by states, which would not be affected by a federal shutdown. However, new reclamation projects that are in the process of being approved by OSMRE would come to a halt.

A shutdown would also stop OSMRE from approving abandoned mine land pilot projects that are intended to create jobs in Appalachian coal country, Joe Pizarchik, who headed the agency under President Barack Obama, told Bloomberg Environment.

Elsewhere at Interior, the Bureau of Land Management, which manages more than 245 million acres of public land, will retain only 1,530 of its 9,260 staffers in the event of a shutdown.