The federal government shutdown could have noticeable impacts on the way public lands are managed, multiple experts told ABC News.
The federal government shut down overnight on Wednesday, leading some conservationists to worry about the disarray that could result from a lack of staffing for federal land.
Short-term impacts on public lands, such as national monuments, national conservation areas, and wilderness, include pileups of trash and human waste as well as vandalism due to a lack of adequate law enforcement, David Feinman, vice president of government affairs at the Conservation Lands Foundation, told ABC News.
"You'll have the element there of little to no staff managing the land," Feinman said.
The National Parks Service's shutdown plan states that parks roads, lookouts, trails and open-air memorials will "generally" remain open to visitors and that law enforcement is an "excepted activity" that is set to continue during the shutdown.
The Bureau of Land Management also plans to evaluate and keep open as many public lands and public facilities as possible, according to its contingency plan.
Parks and visitor sites with accessible areas that collect fees under the Federal Lands Recreation Enhancement Act will utilize available fees to provide basic visitor service, according to the NPS and BLM plans.
"Visitor services including trash collection and toilet cleaning will generally continue at recreation fee sites authorized under the Federal Land Recreation Enhancement Act while funds are available, but may not be available at all locations," the plan states. "BLM land will remain accessible to the public and efforts will be made to post signs, as appropriate, to indicate where services are or are not available."
Feinman said he's concerned about a possible ripple effect on public lands as the shutdown also sidelines personnel who take care of national parks.
Since half of the staff at national parks has been furloughed and access to many parks limited, people may turn to national monuments, national conservation areas and wilderness areas instead -- "a lot of the public lands that are adjacent to and between the national parks," Feinman said.
But there might not be anyone at those locations to manage the land and recreation spots either, which could inconvenience or put visitors at risk, Feinman said.
"There won't be anybody there to clean up trash," Feinman said, describing a worst-case scenario. "There won't be anybody there to help them if there's an emergency."
Feinman advises visitors to remember that there are even less opportunities to throw away trash or use the restroom, so to "pack out what they pack in" to limit degrading the land.
"Don't leave anything on the land, because that's damaging to the land, to the wildlife and to other people who are using the land," Feinman said.
During the 35-day government shutdown in President Donald Trump's first administration, several acts of vandalism on public lands occurred, according to the National Parks Conservation Association. Petroglyphs at Big Bend National Park in Texas were vandalized and irreparably damaged. Joshua Trees -- which are slow to grow -- were chopped down at Joshua Tree National Park in California.
Campgrounds at Death Valley National Park in California and Nevada were kept open, but restrooms were closed, leading to sanitation issues. In addition, illegal off-roading vehicles drove through fragile landscapes.
Human waste and trash overflows became so problematic at Sequoia and Kings Canyon National Parks in California that the parks were forced to close, according to the association.
"There is a history of vandalism during these periods of time, because there's no law enforcement or other land managers who would normally be on the land ensuring that people are not doing things like that," Feinman said.
That shutdown, which lasted from December 2018 to January 2019, was the longest in U.S. history.
This time around, businesses and local communities that depend on access to public lands for economic reasons could struggle to pay their bills, said Chris Hill, CEO of the Conservation Lands Foundation, in a statement.
In addition, people might not be able to hunt, fish, camp and recreate on public lands, and Indigenous communities will not be granted access to their ancestral lands, Hill said.
In a statement, a spokesperson for the Department of the Interior said the department will keep "critical" services such as law enforcement and wildfire units active during the shutdown.
"The Department hopes Congressional Democrats will get serious and agree to fund the government because every day this shutdown continues it is hurting the American people even more," the spokesperson said.
Some experts told ABC News they are concerned the current shutdown could exacerbate the impacts from the federal firings and budget cuts carried out earlier this year.
After taking office in January, Trump established the Department of Government Efficiency (DOGE) with the intention of implementing cost-cutting measures within the federal government.
DOGE then eliminated thousands of federal employees at agencies such as the National Park Service, Bureau of Land Management, National Oceanic and Atmospheric Administration and NASA.
Those cuts continued a decades-long pattern of understaffing federal agencies that manage public lands, Feinman said. Since Trump took office, between 15% and 20% of Bureau of Land Management employees were fired, Feinman said, while 25% of National Park Service employees lost their jobs, according to the National Parks Conservation Association.
On Thursday, Trump threatened mass firings and project cuts should the shutdown continue.
"It's possible that a lot of the people who have been put on temporary furlough for the shutdown might be fired completely by this administration," Feinman said.