Carolina parakeet Carolina parakeets, the only parrots native to the U.S., were officially declared extinct in 1939. (Photo: James St. John/Flickr)

The U.S. learned some harsh lessons about wildlife in the early 20th century. After generations of unchecked hunting, trapping, habitat loss and invasive species, an array of native animals were vanishing. Passenger pigeons, silver trout, California golden bears and Carolina parakeets, to name a few, were all extinct by 1940.

Shocked by these tragedies, Americans began to see the urgency of protecting endangered species. There was still time to save many declining creatures, and one loomed especially large: The bald eagle, America's national icon, was fading from the country it had symbolized since 1782. Up to 100,000 bald eagles nested across the U.S. back then, but by 1963, fewer than 500 nesting pairs were left.

Today, bald eagles are abundant in the U.S. again, as are several other species classified as endangered last century — and that's not just good luck. The U.S. fought its wildlife crisis with a series of laws that eventually led to the bipartisan Endangered Species Act of 1973, a pivotal moment in the history of nature conservation.

The law has helped hundreds of species avoid extinction, and some have recovered enough to be "delisted" from the U.S. endangered list. Not all can bounce back as quickly, though, and while fewer people now shoot or trap endangered wildlife, it does still happen, even as other threats like invasive species, climate change and habitat loss have grown worse. The Endangered Species Act (ESA) is still widely valued by scientists, and a 2015 poll found 90 percent of U.S. voters want it upheld.

bald eagle adult with chick in nest Decades after their steep decline, U.S. bald eagles were declared recovered in 2007. (Photo: Wilfred Marissen/Shutterstock)

Yet the law also has critics, many of whom see it as a barrier to economic activity. Some members of Congress want to weaken or even repeal it, arguing it's ineffective, misused or both. One prominent lawmaker, Republican U.S. Rep. Rob Bishop of Utah, recently told the Associated Press he "would love to invalidate" the law.

"It has never been used for the rehabilitation of species. It's been used for control of the land," said Bishop, who chairs the House Natural Resources Committee. "We've missed the entire purpose of the Endangered Species Act. It has been hijacked."

Efforts to alter the ESA gained little traction under President Obama, but President Trump could be more receptive. While former Trump adviser Myron Ebell isn't part of the administration, he may have hinted at its view during a recent speech in London, describing the law as a "political weapon" that he's "very interested in reforming."

Has the law really gone awry, or are critics crying wolf? To shed some light on the situation, here's a closer look at America's strained relationship with its wildlife:

Where the wild things were

Florida panther crossing sign Roads have become a grave threat to the endangered Florida panther, whose population contains an estimated 180 individuals. Vehicles killed at least 25 Florida panthers across the state in 2014 alone. (Photo: Everglades NPS)

Those who distrust the ESA aren't necessarily anti-wildlife, but they often say the law goes too far, needlessly limiting activities like logging, mining, drilling, cattle grazing and road building. Many want the U.S. to focus on protecting species, not places.

To scientists, however, this view reveals a few misconceptions. Habitat loss is driving a global mass extinction, and it's the No. 1 overall threat to endangered species, points out Eastern Michigan University biology professor Katherine Greenwald.

"That quote made me laugh when I first read it," Greenwald tells MNN, referring to Bishop's quote to the Associated Press. "It speaks to a fundamental lack of understanding of wildlife conservation. Habitat loss is the primary driver of extinctions around the world. Saying you can conserve species without conserving their habitat, that just doesn't make sense to a conservation biologist."

"Wildlife needs somewhere to go," adds David Steen, professor of wildlife biology at Auburn University. "They have habitats they use for migrations, food, finding mates, etc. When we talk about conserving wildlife, we are talking about conserving their way of life and their ecological processes. Otherwise, we could just have animals in zoos and say we've saved the species."

Florida panther at night A Florida panther triggers a motion-detecting wildlife camera near Tampa. (Photo: Florida Fish and Wildlife)

Congress passed the ESA with bipartisan support in 1973 — the House voted 390-12, the Senate 92-0 — and President Richard Nixon signed it into law that December. The plan was always to protect both species and habitats, as the law spells out:

"The purposes of this Act are to provide a means whereby the ecosystems upon which endangered species and threatened species depend may be conserved, [and] to provide a program for the conservation of such endangered species and threatened species."

If a species is threatened or endangered, the government's first duty is to prevent its extinction, then to recover and maintain its population. This job is split between two federal agencies: the Fish and Wildlife Service (FWS) for land or freshwater species, and the National Marine Fisheries Service (NMFS) for marine life.

Under the ESA, it's illegal to kill, harm, harass, trade or transport a listed species, or any products derived from it. The law protects more than 1,600 U.S. species (including subspecies and distinct population segments), along with nearly 700 from other countries, which helps combat the illegal trade of wildlife products.

Otherwise, the onus falls mainly on federal agencies. The FWS or NMFS must develop a science-based recovery plan for U.S. species, as well as identify and protect "critical habitat" key to their survival. This reflects mounting evidence that "protecting species and protecting habitat are two sides of the same coin," says former FWS Director Jamie Rappaport Clark, a wildlife biologist who ran the agency from 1997 to 2001.

"Habitat is everything to wildlife," says Clark, now CEO and president of the nonprofit Defenders of Wildlife. "Whether it's needed for food, shelter or breeding, if you take that away from a species, you're condemning that species to decline and death."

This land is our land

The California condor has become a poster species for endangered species conservation and the fight against extinction. The California condor has become a poster species for the fight against extinction. (Photo: kojihirano/Shutterstock)

While protecting rare wildlife is broadly popular, critical habitat tends to draw more criticism, often due to fears of "land grabs." But that's another misconception.

Critical habitat doesn't create a wildlife refuge or special conservation area, and doesn't affect activities on private land that don't need federal funding or permits. The main effect is on federal agencies, which must consult the FWS or NMFS about any actions they perform, fund or authorize in the habitat to make sure it's safe.

"There is no truth to the notion that it's a land grab," says Brett Hartl, government affairs director for the nonprofit Center for Biological Diversity, a wildlife advocacy group. "Critical habitat doesn't create wilderness, doesn't lock up land and doesn't require a private entity to do anything different than it was doing before.

"It's important to be precise," he adds. "When a species is protected under the Endangered Species Act, everyone has an obligation to not kill it, including private parties. Yes, if you have an endangered species on your land, you can't kill it. That is different, however, from a critical habitat designation."

The only activities affected by critical habitat are those that involve a federal permit, license or funds, and "are likely to destroy or adversely modify" the habitat, the FWS explains. Even when critical habitat does clash with such a project on private land, the FWS works with landowners "to amend their project to allow it to proceed without adversely affecting the critical habitat," adding that most projects "are likely to go forward, but some will be modified to minimize harm to critical habitat."

Critical habitat "remains controversial in terms of what exactly it does," according to Vanderbilt University law professor and ESA expert J.B. Ruhl. It's a confusing legal concept, but also has a dramatic-sounding name. "The term 'critical habitat' itself may instill a sense of, 'Oh, this must be a really big regulatory deal,'" he says.

So what does critical habitat do? It's largely a reminder about a place's ecological significance. "Designation of critical habitat can help focus conservation activities for a listed species," according to the FWS, "by identifying areas that contain physical and biological features that are essential for conservation of the species." It highlights the value of these areas to scientists, the public and land-managing agencies, but it "does not mean the government wants to acquire or control the land."

Room to roam

grizzly bears A grizzly bear sow with her cubs at Grand Teton National Park in Wyoming. (Photo: Chase Dekker/Shutterstock)

Critical habitat has only been designated for about half of the species on the U.S. endangered list, but when it does happen, research suggests it can be a significant boost to recovery. In one study of nearly 1,100 listed species, those with critical habitat for at least two years were more than twice as likely to have an improving population trend, and less than half as likely to be in decline.

Why don't more species have critical habitats? Partly because it's complicated, requiring data on where and how a species lives, along with economic analysis. While the ESA allows only science to inform decisions about listing species, it does require the benefits of critical habitat to be weighed against economic impacts. Faced with a backlog of species to assess, the FWS tends to prioritize that task over habitat designations. Plus, habitat loss doesn't hurt all endangered species equally, and some have bigger problems, like white-nose syndrome in bats or chytrid fungus in frogs.

Critical habitat can also be redundant in terms of regulatory impact, Ruhl says, since the ESA already requires U.S. agencies to consult the FWS or NMFS about activities that might harm a listed species. "There's a huge sense of misunderstanding out there, from everyone involved," he says. "Even some of the environmental advocacy groups pushing for critical habitat probably overestimate the impact."

But that doesn't mean it's pointless, Ruhl adds. By officially marking places key to a species' survival, it can raise awareness and clarify risk. "There may be a symbolic impact, an informational impact," he says, "so it's certainly not inconsequential from that point of view." It can also be designated in historical habitats where a species no longer exists, helping preserve the possibility of its eventual return.

Even though hundreds of listed species lack critical habitat, many nonetheless owe their existence to what's left of some degraded environment. And since the ESA's stated purpose is to save species by saving their ecosystems, those relationships can't be ignored, Clark says, even without the formality of critical habitat.

"Grizzly bears are a good example. They don't have critical habitat designated, but preserving the species absolutely depends on them having contiguous habitat," she says. "Addressing the impacts of endangered species' habitat is a matter of law, regardless of whether critical habitat has been designated."

Baby come back

humpback whale calf in the Caribbean Sea Caribbean Sea humpbacks like this calf are no longer considered at risk, but other populations remain endangered, including those off western Central America and in the western North Pacific. (Photo: Ethan Daniels/Shutterstock)

Another common critique suggests the ESA simply doesn't work, and thus needs an overhaul. As evidence, a bleak-sounding statistic is often cited: Of more than 2,300 total listings (including species, subspecies and distinct population segments), only 47 have been delisted due to recovery, or about 2 percent.

That's true, but it's also a slightly misleading way to measure the law's success. A full recovery is only possible if a species still exists, so the ESA was designed first and foremost to stop extinctions. And it seems competent in that regard: Only 10 of more than 2,300 species have been delisted due to extinction, which means 99 percent have so far avoided the outcome the law was meant to prevent. According to one analysis, at least 227 listed species would now be extinct without the ESA.

"Recovery of endangered species is a slow process," Hartl says, noting that bald eagles and peregrine falcons both needed four decades to recover. "About half of all listed species have been protected for less than 20 years. And if you look at the recovery plans, many were at such precarious levels when they were finally protected, the biology makes it impossible for them to be recovered yet."

The ability for a species to bounce back depends on a wide range of factors, including how low its population fell before receiving protection, how well that protection has been enforced and how quickly the species can reproduce.

"To say species aren't being recovered quickly enough ignores biology," Hartl says. "Scientists know you can't make a northern right whale have 10 calves a year. They can only reproduce as fast as they naturally reproduce."

Still, for whatever reason, the pace of recovery has apparently improved in recent years. Nineteen species were delisted due to recovery under President Obama, more than all previous presidents combined. It's unclear how much credit Obama deserves for that, and conservationists say some species have been delisted prematurely. In general, though, endangered species now show a resilience that was less prevalent in the early 20th century, which at least seems to indicate the ESA isn't broken.

To protect and (con)serve

Florida scrub mint, Dicerandra frutescens The endangered scrub mint, native to just one county in Florida, is rapidly losing habitat to residential and agricultural development. It's one of about 900 flowering plants on the U.S. endangered species list. (Photo: FWS)

Even if the ESA is working, some say wildlife should be protected by the states, not bureaucrats in Washington. But states already are the primary guardians of many rare species, Clark points out; the federal government only steps in as a last resort.

"When everything else fails, the Endangered Species Act comes in to prevent extinction," she says. "It's never something you lead with. Species are listed when state regulatory structures fail, and when states are unable to preserve them."

States keep their own endangered species lists, and state agencies provide an important first line of defense against extinction. But if they bore sole responsibility, the patchwork of policies could be a mess, Clark adds, especially for species that move across state lines. Even in states with political will to save wildlife, budget crises can tempt officials to raid conservation funds or sell off public land.

"There is not one state in the union that has a law as strong and as clear as the Endangered Species Act," she says. "There's no state that has anywhere near the money to do the job well, and they know it. So the devolution to the states is a guarantee that we will just be documenting the extinction of these species."

Congress probably won't launch a direct assault on the ESA, according to Clark, since a slow, cumulative process could be less controversial. "It's going to be death by a thousand cuts," she says, "because the Endangered Species Act polls extremely well."

***

The ESA is renowned for rescuing U.S. bald eagle populations, plus other iconic wildlife like American alligators, brown pelicans and humpback whales. But it also protects a variety of less famous flora and fauna, as well as ancient ecosystems they (and we) rely on. Even if most Americans aren't familiar with all these native species, few would be OK with letting them disappear, both because it's sad and because we'd all share the blame. It's too late to save passenger pigeons or Carolina parakeets from our ancestors, but there is still time to make sure Florida panthers, California condors, whooping cranes and right whales still exist for our descendants.

"All these environmental laws — the Endangered Species Act, the Clean Air Act, the Clean Water Act — were passed as an acknowledgement of an American value," Clark says. "They represent a commitment not only to ourselves, but to future generations. Congress will come and go, I'll come and go, but our children and grandchildren will inherit the legacy of the decisions we make today. It's not about whether I love endangered species; it's about our moral and ethical responsibility to the future."

Russell McLendon ( @russmclendon ) writes about humans and other wildlife.