Jonathan B. Jarvis served for 40 years in the National Parks Service. He worked under presidents of both parties as a ranger, biologist, superintendent, and regional director, and ultimately became the agency's director from 2009–2017.

Jarvis's brother, Destry, has worked with the past 12 NPS directors in various capacities as a conservation advocate. These men know the beauty and wonder of our National Parks well, and their chilling warning about what's happening to these public lands is a must read for all Americans.

In an op-ed published in The Guardian, the Jarvis brothers pulled no punches in their assessment of what has become of the National Parks Service under the current administration. "Under this administration, nothing is sacred as we watch the nation's crown jewels being recut for the rings of robber barons," they began.

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Pointing out that national parks management has been respected by both parties for more than 100 years, they highlighted how unwanted change came swiftly on the heels of the NPS reporting smaller crowd sizes at Trump's inauguration than at Obama's. "Perhaps this is when the NPS wound up on the list of transgressors," the brothers wrote. "Soon the interior secretary, Ryan Zinke, attempted to double the entrance fees, rescinded climate policies and moved seasoned senior national park superintendents around to force their retirements."

Changing leadership has "populated too much of the department's political leadership with unconfirmed, anti-public land sycophants," wrote the Jarvises. But it isn't just the personnel changes that are concerning:

"Then came the decisions to leave the parks open to impacts during the unfortunate government shutdown, illegally misuse entrance fees, open park trails to e-bikes, suppress climate science, kill wolf pups and bear cubs in their dens to enhance 'sport hunting', privatize campgrounds, and issue muzzle memos to park managers. With a waiver of environmental laws, bulldozers are plowing ancient cacti in national parks along the southern border in order to build a wall."

If you read the "kill wolf pups and bear cubs in their dens" part twice, you're not the only one. What that line refers to is the proposal to roll back bans on extreme and inhumane hunting tactics, including shooting bears and wolves—and their babies—in their dens.

"These are not random actions," the Jarvis brothers asserted. "This is a systematic dismantling of a beloved institution, like pulling blocks from a Jenga tower, until it collapses."

Why, though? Why would someone want to dismantle the National Parks Service that has worked so well and is one of the United States' most beloved achievements?

"Because," wrote the Jarvises, "if you want to drill, mine and exploit the public estate for the benefit of the industry, the last thing you want is a popular and respected agency's voice raising alarms on behalf of conservation and historic preservation."

Because if you want the public to ignore the science of climate change, the last thing you want are trusted park rangers speaking the truth to park visitors.

Because if you want to get the federal government small enough (in the words of Grover Norquist) to 'drown it in a bathtub', the last thing you want is a government agency with high popular appeal that needs to grow rather than shrink."

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The brothers closed their piece by recommending that, "when this nightmare ends, and we begin to rebuild," Congress make the National Parks Service into an independent institution like the Smithsonian. That way it will "no longer subject to the vicissitudes of a hostile political agenda in a Department of the Interior dominated by extractive industries and anti-public land crusaders."

Our national parks feel like something that should be untouchable, transcending the melee of partisan politics as a matter of course. And yet, here we are.

As one person pointed out, many of the proposed changes referred to in the op-ed have been stymied due to public outcry and lawsuits. So let's keep using our voices to defend the public lands we've all inherited and demand that our government keep up its stewardship responsibilities. And of course, keep supporting the organizations dedicated to conserving and protecting our planet in all its beauty and wonder.