In recent years, the Trump administration has repeatedly tried to cut the ESA, claiming that strict rules are throttling development and impeding “energy domination.” Executive orders signed this year have called for agency rule changes that could accelerate fossil fuel development by short-circuiting environmental reviews.

Burgum and other conservatives argue the law is a failure, with rules so rigid that they offer little incentive for species to recover. Scientists and legal experts say, however, that the problem is not the ESA’s requirements but the decades of underfunding and political whiplash.

“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.”

A Record of Prevention, Not Just Recovery

Despite such criticisms, experts say the ESA has helped prevent mass extinctions. While just 26 species have gone extinct under federal protection since 1973, at least 47 more have disappeared after being petitioned for listing, and more than 2,000 are on the 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.”

The Act’s biggest success story is the bald eagle, which after DDT bans and new protections under the ESA in 1978 has returned to precolonial levels. In the 1960s, there were fewer than 500 nesting pairs in the lower 48 states, but by the time the eagle was removed from the endangered list in 2007 there were nearly 10,000.

American alligators and Steller sea lions have also made impressive comebacks, and in 2016 the Greater sage-grouse became the first species to be removed from the ESA after conservation measures were put in place.

The ESA’s protections on private property have been a particular source of contention over the years, as the law can restrict how land is used and lead to prosecution in cases of violations.

“The ESA interferes with people’s expectations on how they can use that land,” said Jonathan Adler, a professor of environmental law at William & Mary. “That’s a major disincentive to cooperation on the part of the landowner.”

Some research indicates such rules may even lead to “perverse incentives.” A study on red-cockaded woodpeckers, for example, found timber was more likely to be harvested in the early stages of stand growth if the bird was known to live in the area, likely to pre-empt federal habitat restrictions.

Congress has tried to offer landowners tax breaks and other incentives to set aside habitat, but those efforts have waned in recent years, with many on the left and the right concerned the ESA doesn’t do enough to protect the places where most species live.

The Endangered Species Act has seen its ups and downs politically, with wide bipartisan support in its early years but becoming one of the most litigated environmental laws in the country. Every administration since George H.W. Bush has seen attempts to cut the ESA, usually rolled back when the administration changed.

Today, some experts fear the Trump administration’s aggressive rollbacks of protections combined with a conservative-leaning Supreme Court could permanently curb the ESA’s powers. Climate change and habitat destruction continue to drive more species toward crisis levels, adding to concern.

Harvard Law School’s Andrew Mergen, who spent two decades as an assistant regional director of endangered species litigation with the Department of the Interior, said focus should be on ramping up resources, not loosening rules.

“The law has been tremendously successful at preventing extinctions,” he said. “The real challenge is committing the money and political will to see species recover, not dismantling the mechanisms that have kept them from going extinct.”

The fact that a species was removed from the endangered list this year, under Trump’s watch, was touted by the administration as proof that the ESA isn’t really “Hotel California.”

In July, the U.S. Fish and Wildlife Service announced that the Roanoke logperch, a freshwater fish, had recovered enough to be delisted. Burgum called it “proof positive that ESA is no longer the ‘Hotel California’ from which no species can check out,” and was also “a harbinger of many more to come.”

But conservationists point out that the recovery took more than three decades of dam removals, wetland restoration, and other habitat improvements, as well as costly reintroduction efforts to boost the fish population—all started long before Trump took office.

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