The ESA has come under frequent attack from the Trump administration, which since January has issued multiple executive orders arguing that overregulation hampers development and prevents “energy domination.” Orders this year call on federal agencies to rewrite ESA regulations in ways that would expedite fossil fuel development and skirt mandatory environmental reviews.

Burgum and other conservatives have labeled the law as broken, with its stringent rules achieving little in the way of promoting species recovery. However, experts point out the law itself isn’t broken, and the challenge has long been inconsistent political will and underfunding.

“We continue to wait until species are in dire straits before we protect them,” said David Wilcove, professor of ecology and evolutionary biology at Princeton University. “That makes recovery far more difficult and expensive.”

Experts point out the law’s biggest successes have often come in the form of preventing total extinctions. Since the law’s passage in 1973, only 26 species on the list have gone extinct while under federal protection. In contrast, at least 47 species are known to have disappeared while waiting to be listed.

“The ESA works more like a critical care unit than a hotel,” Wilcove said. “It’s as though we built a great hospital but never funded enough doctors or equipment.”

One of the ESA’s most famous success stories has been the recovery of the bald eagle. In the 1960s, overuse of the pesticide DDT combined with habitat loss had left only a few hundred breeding pairs in the lower 48 states. After a nationwide DDT ban and ESA protections in 1978, numbers slowly improved, and by 2007 the eagle was removed from the list with almost 10,000 pairs nesting across the country.

The law has also helped other species recover, including the American alligator and the Steller sea lion, by providing additional protections.

Since ESA protections apply to private land as well as public, landowners often feel targeted and voice strong objections. More than two-thirds of listed species live on private lands, and about 10 percent are found there exclusively.

“If you own land and put an endangered species on it, your ability to use that land is going to be limited, and you can be prosecuted,” said Jonathan Adler, professor of environmental law at the William & Mary Law School. “That obviously discourages landowners from cooperating.”

Some researchers say such rules can even create “perverse incentives.” A study on the red-cockaded woodpecker found, for instance, that timberland was more likely to be harvested early in the areas where the bird lived, possibly to avoid having their property classified as federal habitat.

Over the years, lawmakers have tried to smooth relations with incentives like tax breaks and conservation easements that compensate landowners for setting aside habitat. Such programs have been on the decline in recent years, worrying some conservationists.

The Endangered Species Act was once a bipartisan endeavor, but now it’s among the most litigated environmental laws in the country. At least three administrations have tried to weaken the ESA, but those rollbacks have usually been undone by subsequent administrations.

Conservationists fear Trump’s current attacks, when paired with a conservative Supreme Court, could permanently narrow the law’s scope. Meanwhile, habitat loss and climate change continue to drive more species toward extinction levels.

Andrew Mergen, who worked at the U.S. Department of the Interior and the U.S. Department of Justice litigating ESA cases for decades before joining the Environmental and Natural Resources Law Program at Harvard Law School, said he thinks the debate should be less about new regulations and more about funding. “The law has done its job in terms of preventing extinctions,” he said. “The real challenge is devoting the political will and resources to getting species off the list, not chipping away at the protections that keep them alive.”

For all the politics swirling around the ESA, recent developments on a handful of species give an idea of what’s possible. The U.S. Fish and Wildlife Service announced in July that the Roanoke logperch, a freshwater fish, has recovered enough to be taken off the endangered list. Burgum cited the announcement as “proof” that the ESA is no longer like “Hotel California.”

Conservationists said it’s a win, but one that took three decades of dam removals, wetland restoration, and ultimately a $600,000 reintroduction effort from a hatchery. The fish, which was first protected under the ESA in the 1980s, first disappeared from its Roanoke, Virginia, birthplace in the early 1970s due to unregulated damming and mining.

“The optimistic part is we know what to do to save species,” Wilcove said. “If we invest in them, we can recover them. The question is whether we will.”