A former superintendent of Joshua Tree National Park warned that the damage of the government shutdown could last 200 to 300 years.

While most park employees were unable to work, visitors were found off-roading illegally, cutting down centuries-old trees, and leaving restrooms overflowing with trash and human waste.

A few days after the shutdown, park rangers discovered newly-carved unauthorized trails and evidence of illegal campfires.

These activities could mean irreparable harm to the local ecosystem and present a huge financial challenge.

Few national parks have been hit harder by the government shutdown than Joshua Tree National Park, a nearly 800,000-acre protected area in Southern California known for its rocky landscape and stunning throng of centuries-old trees.

Days after the shutdown came to a close, park officials found evidence of hundreds of illegal campfires and about 20 miles of unauthorized trails formed by off-roading vehicles. A visitor also posted a video of mounds of trash, including discarded furniture, cardboard boxes, and even a vacuum cleaner, all piled along the road.

Read more: The government shutdown may be over, but the damage to national parks like Joshua Tree and Yellowstone could be permanent

With most park employees unable to work during the shutdown, many visitors were left unchecked, leading to a Wild West of human activity in certain areas.

Almost immediately after the shutdown began, parkgoers began seeing restrooms overflowing with trash and human waste. Reports surfaced of visitors defacing rocks with graffiti, camping illegally, cutting down beloved Joshua trees, and skirting entrance fees, which are supposed to go toward visitor services.

The activity forced the park to temporarily close its campgrounds, though the rest of the park managed to remain open to visitors.

One of the park's former superintendents is now warning that the damage could last for centuries.

On Saturday, the day after President Donald Trump signed a bill to end the shutdown, protesters gathered near Joshua Tree to lament the destruction of the public land.

Speaking before a large crowd, the former superintendent, Curt Sauer, painted a picture of what happened during the shutdown.

According to Sauer, Joshua Tree had been forced to operate with only 40% of its maintenance staff and 20% of its resource-management scientists. He said the park diverted $300,000 in entrance fees — which were supposed to go toward maintaining trails, upgrading campgrounds, and building a new visitors center — to continue operations while employees were furloughed, or temporarily laid off.

Rangers discovered evidence of hundreds of illegal campfires. Gina Ferazzi/Los AngelesTimes/Getty Images

"What's happened to our park in the last 34 days is irreparable for the next 200 to 300 years," he said.

In a statement to Business Insider, John Garder, a senior director of the National Parks Conservation Association, agreed that some of the damage could be permanent.

"Some damage can be repaired, but some things can be lost forever," Garder said. Of particular concern, he added, was the possibility of vandalized historical sites or the looting of irreplaceable artifacts.

The environmental damage could also be long-lasting.

During the shutdown, there were at least three reports of Joshua trees being cut down to make room for illegal off-roading in restricted zones. Rangers are now attempting to determine how many trees were destroyed.

A Joshua tree was severed in half. Gina Ferazzi/Los AngelesTimes/Getty Images

In addition to being the park's namesake, the trees are a key part of the Southern California ecosystem, providing vital support to birds, bats, and insects, among other forms of wildlife.

"When a mature tree is cut down, an ancient organism has been killed, and it could be centuries before another takes its place," a director of the Mojave Desert Land Trust told the Desert Sun.

According to Garder, off-roading can also damage the "biological crust on the soil that supports a web of life."

If Joshua Tree National Park hopes to repair this damage, it will have to pull from an already waning pool of funding.

The NPCA estimated that the National Parks Service faces more than $13 million in uncollected entrance-fee revenue as a result of the shutdown, on top of a $11.6 billion repairs backlog.

At the rally on Saturday, Sauer estimated that Joshua Tree had lost about $800,000 during the shutdown. A park spokesman told the Los Angeles Times that the losses could be even higher — around $1 million.

A day after the rally, Trump suggested that another shutdown could be on the horizon.