Attacks on the ESA have ramped up since January, with the Trump administration arguing that the law’s strictures hobble development and prevent “energy domination.” In a pair of executive orders this year, Trump instructed federal agencies to rewrite ESA regulations to “cut red tape” and “promote predictability,” language that conservation groups fear will open the door to fast-tracking fossil fuel projects without the environmental review normally required.

Burgum and other conservatives have argued that the law itself is broken, with stringent rules that do little to encourage species recovery. But scientists and policy analysts say that the law isn’t the problem. Rather, the ESA is hamstrung by long-standing underfunding and shifting political priorities.

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

Critics may lament the ESA’s recovery record, but experts say they shouldn’t overlook the thousands of species the law has already helped. Although the ESA has protected more than 1,600 species since 1973, only 26 listed species have become extinct under federal protection. By contrast, at least 47 species are thought to have disappeared entirely after being placed on the agency’s waiting list.

“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.”

For example, take the bald eagle. In the 1960s, the chemical DDT, along with rampant habitat loss, had left just a few hundred nesting pairs of the country’s national bird in the lower 48 states. In 1978, DDT was banned and the bird was added to the ESA, triggering protective measures like habitat conservation and restrictions on hunters. In just 30 years, bald eagle numbers had rebounded enough that the species was removed from the list in 2007, with almost 10,000 pairs flourishing across the country.

Other formerly threatened or endangered species, such as American alligators and Steller sea lions, have also made remarkable comebacks.

The ESA guarantees protections for threatened and endangered species on both public and private lands, a detail that has proved politically contentious for decades. More than two-thirds of listed species depend on private lands for some or all of their range, while roughly 10 percent of listed species exist almost exclusively on private property.

“The plain fact is that your ability to use that land is going to be limited, and you can be prosecuted for that,” said Jonathan Adler, a professor of environmental law at the University of Maryland School of Law and the University of Virginia School of Law. “That obviously discourages landowners from being cooperative.”

Some studies have even suggested these rules create “perverse incentives” that could end up hastening a species’ decline. One found that when timber companies learned of an endangered species presence on private lands, they harvested red-cockaded woodpecker habitat early to avoid federal habitat regulations.

Congress has tried, over the years, to create incentives for landowners to protect private habitats, such as tax breaks and conservation easements, which pay landowners for leaving their property undeveloped. Those programs have since waned, which conservationists worry could hamper conservation efforts going forward.

The ESA, once a bipartisan darling, is now one of the most litigated environmental laws in the country. Since its passage in 1973, administrations of both parties have tried to roll back its protections, though such efforts have been relatively minor until Trump took office. A coalition of environmental groups is now challenging some of his more sweeping changes in court.

Conservationists fear that the combination of Trump’s regulatory rollback and a conservative-leaning Supreme Court could leave the ESA a shell of its former self. At the same time, ongoing development and climate change continue to exacerbate habitat loss, placing ever more species on the endangered list at the federal government’s already overburdened wildlife agency.

Andrew Mergen, a senior policy scientist at Harvard Law School who previously litigated dozens of ESA cases, said that the main focus should be on funding levels, not further deregulation. “The law has prevented extinctions,” he said. “The real challenge is committing enough money and political will to help these species recover, not taking apart the protections that keep them alive.”

Politically, the ESA has been waging a losing battle on several fronts. But after decades of cuts and redirection, there may be reason for cautious optimism. In July, the U.S. Fish and Wildlife Service declared that the Roanoke logperch, a freshwater fish, has recovered sufficiently to be removed from the endangered species list. Burgum, in a statement, called the fish “proof that the ESA is no longer ‘Hotel California.’”

Conservationists say the fish’s recovery, which took more than 30 years, was made possible by the aggressive dam removals, wetland restoration and expensive reintroduction efforts that began long before the Trump administration. And while individual species may be able to pull through with sufficient funding and political will, it’s unclear whether there’s enough of either in the current political climate.

“The optimistic part,” Wilcove said, “is that we know how to save species if we invest in them. The question is whether we’ll make that commitment.”