WASHINGTON/JOSHUA TREE NATIONAL PARK, Calif. (Reuters) - As Ralph Snake walked across Washington’s National Mall on Wednesday, he stopped every few feet to pick up litter that has accumulated in the once-tidy expanse of grass since a budget showdown partially closed the federal government 12 days ago.

The figure of a panda is seen behind a sign telling the public that the National Zoo is closed due to the partial government shutdown in Washington, U.S., January 2, 2019. REUTERS/Kevin Lamarque

“I decided to clean up this one section, because that’s what Americans will do,” said Snake, a 64-year-old member of the indigenous Ho-Chunk Nation in Wisconsin.

Snake came to the U.S. capital to witness Sharice Davids get sworn in as one of the first two women of native American descent to become members of Congress.

The partial shutdown, which has cut off many government services, entered its 12th day on Wednesday with no end in sight. It stems from an impasse between congressional Democrats, who control the House of Representatives as of Thursday, and President Donald Trump, who is demanding $5.6 billion in funding for a wall on the U.S. border with Mexico.

National parks have closed campgrounds out of fear that toilets will overflow with human waste. Hundreds of thousands of federal employees are working without pay. The immigration court system, already suffocating under a backlog, is largely shuttered.

The prospects for an end to the showdown remained unclear, even as congressional leaders visited the White House on Wednesday.

In Washington, the 17 museums run by the Smithsonian as well as the National Zoo closed their doors on Wednesday after running out of emergency funding, leaving tourists frustrated with politicians of both parties.

“It’s stupid,” said Laura Vanbragt, a 20-year-old student from Grand Rapids, Michigan. “There should just be more communication between the two, more give on both sides.”

Outside the Bureau of Engraving and Printing, Clint Woods and his family stood waiting for a guided tour with other visitors who were locked out of more popular venues.

“It’s like two squabbling children,” Woods, 43, said of Trump and Democratic leaders in Congress. “They both think they’re right, and they’re dug in.”

At Joshua Tree National Park, which is named after the spiked yucca plants that grow all over the park’s desert landscape, roads and scenic turnouts were full of cars on Wednesday but campgrounds were closed.

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Rock climbers Kiera Waskey, 21, and Stefan Nelson, 22, were able to camp in the park for three nights after arriving on a visit from Minnesota.

“We were told that today we had to clean up camp and we can’t camp here anymore, which was a bummer,” Waskey said, standing near rock outcroppings dotted by several climbers.

“I guess we take it for granted almost, these beautiful places that we have and we never thought we’d have to prepare for it (the shutdown),” he said.

Public bathrooms and trash bins at the park were well kept, because volunteers were cleaning them, visitors said.

The booth at the park’s entrance was closed, so visitors were able to roll in without paying an entrance fee.

Frequent park visitors Marie Hoffman and Trevor Goodman, who are both 19 and students at University of California, Davis, said they noticed a lot more climbers and general visitor than they normally see at the park.

“It looks like Disneyland today with just all the cars and everything, so many visitors,” Hoffman said, attributing the increased traffic to the temporary lack of an entrance fee.

WORKING WITHOUT PAY

Unlike in some previous government shutdowns, many national parks have remained open, though without staff to collect trash and service restrooms. Advocates have voiced alarm that an extended shutdown could cause environmental damage.

“We’re very concerned about the reports we’re seeing of human waste in inappropriate places,” said John Garder, senior director of budget and appropriations for the National Parks Conservation Association. “Trash is a serious concern for wildlife.”

The impact of the shutdown has reached the nation’s 62 immigration courts as well. Hundreds of judges are on furlough, and only cases of immigrants in detention are being heard.

The Trump administration has expanded the system, which is run by the U.S. Department of Justice, aiming to cut down on the backlog of more than 800,000 cases, but the shutdown will complicate that effort, said Ashley Tabaddor, the president of the national immigration judges’ union.

“To reschedule these cases can take several years because the judges are all booked,” she said.

A Justice Department spokesman said he could not respond to a request for comment because of the shutdown.

Meanwhile, some 800,000 government workers are either furloughed or working without pay until the shutdown ends.

Shekina Givens, a 32-year-old Transportation Security Administration officer in Atlanta and president of the local chapter of a union that represents government employees, said she is avoiding using her credit cards and putting off some expenses.

“I’m the only person that’s working in my household and paying all the bills,” she said.