PALAU, Micronesia — The ride out to sea was, in a word, unpleasant. The coastal waters of Palau, an island nation in the western Pacific, are typically calm and electric blue, like what you might see on a screensaver or postcard. The country has put in place some of the world’s most rigorous protections to keep its marine environment pristine.

But on this particular morning in July, a super typhoon named Bavi was churning north of us in the Philippine Sea. Clouds darkened the water and battered us with rain as our boat seesawed through the swell toward the horizon. 

Our destination was what you might call a coral garden — a patch of coral, about two miles from shore, that scientists had planted over the past couple of years in an effort to rebuild a damaged reef. 

I was wet, cold, and nauseated when we arrived. So naturally, I strapped on a mask and jumped in. 

Below me, I could see dozens of star-shaped metal structures that researchers had attached to the seafloor. They were studded with corals in all forms and colors: neon blue antlers, fluffy green mittens, baseball-sized brains. Some of the corals looked like a collection of human vertebrae. Others resembled miniature pine forests. 

In the past two decades, governments, nonprofits, and even hotels around the world have dedicated hundreds of millions of dollars to replanting coral reefs like this one. Reefs are among the planet’s most endangered ecosystems: Rising ocean temperatures, pollution, and other threats have killed off an estimated 50 percent of live coral globally since the 1950s.

Those steep losses erode the irreplaceable benefits that coral reefs provide. They go far beyond tourism. Healthy reefs lessen coastal flooding from storms like Bavi. They also serve as nurseries and homes for larger animal species, such as endangered sea turtles and valuable fish like snappers and groupers that people eat. 

That’s why so much time and money has gone into restoring these ecosystems globally. Including here in Palau. A different typhoon and warming waters had destroyed some of the region’s coral many years ago, which caused the local fishery to decline, according to Sharp Sakuma, the governor of Ngaraard, a Palauan state where the coral garden is located. “It’s our food,” Sakuma said of fisheries. So a few years ago, he asked local researchers to help bring the reef back.

But reef restoration has a fatal flaw. 

Rising global temperatures are heating up the ocean and fueling marine heat waves, which kill reefs. That means that much of the coral that people painstakingly plant often ends up dying months or years later — simply because the ocean is too hot. It’s like planting trees to restore a forest that will soon burn in a wildfire. And this raises serious doubts about the role reef restoration can play in the recovery, and ultimate survival, of these iconic ecosystems.

The colorful antlers, mittens, and brains below me, however, were not your typical planted corals. 

They were different. 

And they may offer a new reason for hope.

These corals had all gone through what you might call a fitness test. In a lab on shore, marine scientists exposed them to extreme heat and scored them for their ability to tolerate warming. Corals on some of the metal stars here got top marks — they appeared resistant to heat. Those individuals may have more of a fighting chance at surviving as ocean temperatures rise. 

These sorts of fitness tests for corals are inexpensive and unexpectedly low-tech: They take place in cheap, store-bought picnic coolers, like what you might bring to the park. But by helping researchers identify the hardiest corals, these tests could help overcome one of reef restoration’s greatest challenges. 

Subjecting corals to hot water in a plastic cooler may sound ridiculous. Until you consider the stakes and the circumstances: As the planet warms, simply protecting our beloved, life-supporting places is no longer enough to save them. Neither is restoring them to some former state.

To truly help coral reefs endure, we may actually need to reengineer them.

Scattered across a remote stretch of the Pacific is a collection of more than 300 islands, which, together, form the nation of Palau. Many of those islands are no larger than a small house. And because they’re eroding at the base, they look as though they’re floating above the ocean. When you’re out at sea, it’s easy to pretend that you’re flying through the floating mountains of Avatar’s Pandora.

But the real magic is, without a doubt, underwater. 

Palau is surrounded by a vast network of coral reefs, many of which are in near-perfect condition. The region has more than 400 coral species — for comparison, the Caribbean has about 70 — which form the base of a thriving marine ecosystem. On just one weekend of diving there, I encountered close to 100 sharks, more than a dozen sea turtles, and three enormous manta rays. (In my more than 20 years of diving, I’ve rarely seen such an abundance of sea life.)

In the last two decades, Palau has become an epicenter for research on how warming affects coral reefs. Part of that is practical: The country’s abundant corals allow scientists to study how different species and populations respond to rising temperatures. It’s also home to a well-equipped marine lab, the Palau International Coral Reef Center.

But there’s also an urgent local need. Palau is deeply dependent on its coral reefs: Its fisheries and tourism make up more than a quarter of the country’s GDP. And while Palau is home to one of the world’s largest marine protected areas — which bans commercial fishing across 80 percent of its national waters — that does little to protect the reefs here from the existential global threat of ocean warming.

Why is heat such a dire problem?

One “coral” is not a single animal but a colony of hundreds or thousands of individual animals, known as polyps. Those polyps are all nearly genetically identical. They grow the colony — the coral structure that you see on a reef — by cloning themselves over and over again.

Polyps fuel themselves, in part, by grabbing particles out of the water with tentacles (up close, polyps look a bit like sea anemones). But most of their food, and much of their color, comes from a kind of algae that lives within their cells. Like plants, that algae photosynthesizes. And it passes the solar energy it generates onto the coral, in return for nutrients and a place to live.

This partnership fails under extreme heat.

When the ocean is too warm, the algae malfunction, and the polyps kick them out. As a result, the corals lose their primary source of food and their iconic color. That’s bleaching. A bleached coral is not dead but starving, and it will die unless the water cools back down. 

Yet there’s another key detail here: Some corals seem to resist this heat-fueled bleaching. They appear naturally more tolerant to warming than their peers. And you can actually see this when you’re snorkeling during a heat wave: Some corals will be bone white, whereas other colonies of the same species nearby will appear fully saturated. Heat tolerance is a trait with natural variation, like height or eye color in humans. 

It’s this detail that underpins efforts to make reef restoration less futile in a warming world. If scientists can find local corals that can tolerate warming, they can use them to regrow native reefs that might endure some degree of climate change, here and anywhere coral reefs can be found. 

What scientists in Palau are trying to demonstrate is how — absent a naturally occurring heat wave — you can identify those heat-tolerant colonies.

On a mostly clear afternoon in July, days before the typhoon grazed Palau, I boated out to a shallow reef with Steve Palumbi, a marine ecologist at Stanford University. He’s tall and thin and has white hair that he often pulls back into a short ponytail. 

Once the boat dropped its anchor in the sand, Palumbi and I jumped in, along with three researchers from the Palau International Coral Reef Center (PICRC). I felt like I was swimming in a tropical fish tank. The water was clear and full of silvery fish. A carpet of colorful coral coated the seafloor. Every hole and crevice was occupied — by a giant clam, a spiky starfish, a sea cucumber, a furry crab. The reef was a giant apartment building with a cast of unusual tenants.

I followed Palumbi and the PICRC researchers over to metal structures on the reef that his team had built. They looked like sunken bed frames, and like those metal stars, they were covered in pieces of coral.

These corals are some of Palumbi’s guinea pigs. 

Over the last two years, researchers in his lab at Stanford have been subjecting them to a variety of different heat tests and scoring their performance. The concept is simple: Put the corals in a tank, crank up the temperature, and measure how quickly each one bleaches. The colonies that stay colorful as the temperature soars — the “winners” — may be more tolerant to warming.

There are several different ways to measure a coral’s tolerance to warming in a lab. Some tests expose corals to moderately high temperatures over weeks, whereas others blast them with extreme heat over days, or even hours. Longer-lasting tests tend to better represent a natural heat wave — what corals will actually face in the years to come. But they’re expensive, time-consuming, and require expertise. That’s a problem for people who are racing to rebuild damaged reefs, especially in poor regions that lack fancy marine labs and funding.

Working with PICRC, the Nature Conservancy, and other partners, Palumbi’s lab has been trying to demonstrate that the quick and cheap version of these heat tests — using picnic coolers to pressure-test corals over a few days — works well enough. They can help identify heat-tolerant corals and, thus, improve reef restoration, all within one work week, and on a low budget. 

That afternoon, Palumbi was collecting corals from those metal frames to test at PICRC. Using wire cutters, Palumbi and the other researchers snapped off branches of coral from the individual colonies. Breaking fragments of coral off a colony is not unlike taking clippings from plants — the “donor” colony continues to grow, even as parts of it are removed. 

After filling plastic bins with dozens of coral fragments across three species, the researchers brought them to the boat, loaded them into a large container full of seawater, and then we headed back to shore. 

It is hard to put a price tag on coral reefs, but those who have tried say it is quite a lot.

The authors of one study published in 2024 estimated that reefs in the Asia Pacific, which includes Palau, Australia, and Indonesia, among other countries, contribute about $25 billion a year on average to the region’s economies for their role in supporting fisheries and tourism alone. 

That doesn’t include the damage that reefs offset during tropical storms. Coral reefs are self-regenerating seawalls that can reduce wave energy — dulling the fiercest brunt of a hurricane making landfall, for example — by an average of 97 percent. In the US, economists estimate that reefs save the country more than $1.8 billion a year just in avoided flood damage. Globally, the cost savings from coral reefs are far higher. 

So it’s no surprise that people are so eager to rebuild reefs when they collapse.

To restore these ecosystems, people typically harvest fragments of coral from the wild and grow them in a tank on land or in a “nursery” in the ocean. Then they plant them, one piece at a time, on the seafloor, often using an adhesive putty. 

Reef restoration has grown into a global project of enormous scale: A network called the Coral Restoration Consortium counts more than 900 reef restoration efforts worldwide led by more than 350 organizations. By one estimate, groups have spent more than $250 million on reef restoration over roughly the last decade. 

But as important as those efforts may be, many of them haven’t worked — they haven’t actually helped coral reefs grow back. “Show me a square mile of reef that has been [successfully] restored,” Palumbi said. “There isn’t one.” 

At the heart of that failure is climate change: Prolonged bleaching kills off much of the planted coral, undoing a tremendous amount of effort.

One of the most extreme examples of this is in Florida. In the last three decades, organizations have planted tens of thousands of corals in the Florida Keys, which is home to the world’s third-largest barrier reef. I visited in 2022 and saw the progress of restoration firsthand — there were beautiful fields of planted staghorn and elkhorn, two federally threatened coral species. Some colonies were more than a meter wide. I wrote a story about how it was reviving Florida’s reef. 

Then in summer 2023, a record-breaking heat wave struck. The reefs turned a ghostly white. And eventually, nearly all of the staghorn and elkhorn coral in the Florida Keys — including the vast swaths of replanted corals — died, becoming functionally extinct. It was one of the more devastating things I’ve seen in my time covering the biodiversity crisis.

There are similar examples from around the world — in Colombia and Costa Rica, for example, along with Indonesia and the Seychelles. 

It’s not that restoration groups are unaware of this problem. Scientists have been studying bleaching for many years in search of solutions. In Florida, researchers are testing out what happens if you cross-breed corals from South Florida with colonies from a warm reef in Honduras, which have a natural ability to withstand higher temperatures. Perhaps their hybrid babies will be more likely to survive the next heat wave. But most of these approaches are time-intensive, costly, run by teams of PhDs, or stuck in the lab.

“The lab science is cool,” Palumbi told me. “But it’s going too slowly. We don’t have time to wait.”

The outdoor research space at PICRC looked like a typical marine lab — a labyrinth of pipes and pumps and, of course, tanks full of sea creatures, which in this case included corals, urchins, and giant clams that would abruptly close if you got too close. It looked appropriately science-y. With the exception of one wooden shelf. On it were eight blue and red plastic picnic coolers, in which Palumbi’s team is doing the bulk of its heat testing.  

After returning to shore with bins full of coral fragments, Palumbi put some of them into the coolers, which were fitted with small heaters and pumps. The water inside was around 30 degrees C (86 degrees F). That’s the average high temperature for waters in this region, and the baseline for the test he was about to run.

Then Palumbi, rather unceremoniously, cranked up the dial. 

Over each of the next four days, the water in half of the coolers would hit a higher temperature, before returning to the baseline of 30 degrees. On day one, for example, it would reach 34; on day two, it would hit 35; and so on. And each morning, Palumbi would assess the fragments for bleaching. Although these tests run for only a few days, they’re meant to mimic what some corals might experience at low tide during a heat wave, Palumbi said.

I visited the lab early one morning, after just one day of heat stress — after the coolers had reached 34 degrees. Palumbi laid the fragments out on a white grid to evaluate their color, ranking them from one (no bleaching) to five (fully bleached). They were shaped like twigs and still had their normal orangy brown color. No bleaching yet. By the next morning, however, the corals appeared more varied: Some were starting to pale and others remained saturated.

On the last morning of the test — after the coolers had reached 37 degrees, or close to 100 degrees F — nearly all the fragments were white, resembling cauliflower florets. They had expelled their algae. And yet a handful of the fragments still appeared mostly brown. Even after getting blasted by extreme heat, they hadn’t bleached. 

“Those are the champions,” Palumbi said.

Palumbi believes that quick heat tests like this stand to benefit restoration projects across the tropics. The equipment, including four coolers, costs less than $1,000, according to Courtney Klepac, a researcher in Palumbi’s lab, who studies heat testing. Groups that are rebuilding reefs can essentially run the corals they harvest through these tests, and then only plant the champions. 

That’s precisely the idea behind a project Klepac leads called the Coral Futures Academy. She’s been helping environmental groups across the Pacific integrate these low-overhead heat tests into local reef restoration efforts. And these actually include the coral garden I snorkeled during the typhoon: All the pieces of coral there had gone through similar heat tests. 

As promising as this approach sounds, however, there is an important caveat: These tests are only useful if they actually predict which corals are more likely to survive under real-world warming. And so far, scientists haven’t proven that. 

Previous studies comparing short heat tests to those that are longer and more faithfully replicate a real heat wave show mixed results; the winners of one are often not the winners of the other. It suggests that surviving a short blast of heat requires different skills than withstanding warmth that lasts for weeks. 

Some researchers have also measured what happens to corals that went through an even faster one-day test after they were put in the ocean and then experienced a real heat wave. The champions in those rapid tests were not always more heat-tolerant in the wild. 

Ilan Bubb, a marine biologist at the University of Amsterdam who’s studied heat tests, says it’s like trying to predict a person’s marathon time based on how well they perform in a sprint. “We know there’s some correlation there, but how good is that correlation?” he said. “How much information you can get about that marathon from a hundred-meter sprint is still just undetermined.” 

Palumbi, Klepac, and their colleagues have been exploring this question, too. They’ve compared bleaching scores from heat tests that last for three or four days to those that last for roughly two weeks. The results appear to be similar, Klepac said: On average, the same corals resisted or succumbed to bleaching in both experiments.

Klepac has also studied what happens to heat-tested corals when an actual marine heat wave hits. At the coral garden I visited with those metal stars, PICRC researchers planted the heat-test winners as well as the poorer performers, as a point of comparison. And as Klepac’s unpublished research shows, the winners of the short heat tests survived better during a bleaching event in Palau in 2024, compared to the losers. 

“I am probably one of the few people that you will talk to that kind of low-key gets a little excited for bleaching events,” Klepac told me. “It is a very true test of what we’ve been doing. If we’re trying to market this approach, I want to feel confident that what we’re prescribing actually works.”

There are other drawbacks to this testing approach. For one, it relies on a visible trait — whether a coral resists bleaching or not. That trait, however, doesn’t always indicate whether the coral has the genes to resist bleaching. The colony may have just been healthier going into the test than its peers. Two runners, for example, might get different times in a 100-meter sprint, not just because of their genes but because of how much rest they got the night before. 

This matters when you’re trying to rebuild a reef: Typically, you want the coral colonies you plant to eventually reproduce and create heat-tolerant babies. That only happens if the parents have heat-tolerant genes. 

And there are other traits that corals need to survive, beyond the ability to withstand warming. 

“It’s not just about heat tolerance,” said Liam Lachs, a coral researcher at University of Queensland in Australia who has extensively studied the value of different heat tests. 

By only planting the corals that perform well on these heat tests, you might miss colonies that have other important strengths, such as the ability to withstand disease. In fact, future research may reveal that testing corals for one of these other traits may ultimately be a better predictor of their survival in the era of climate change, says James Guest, a reef ecologist at Newcastle University in England.

Palumbi readily admits that the short picnic cooler tests are not perfect. But the important question, he says, is whether they are good enough — good enough to start using them now to help reefs as the science around fitness testing gradually improves. 

That much is clear, he says, and several other researchers I spoke to agreed. While the utility and accuracy of short heat tests is not yet proven, people who want to rebuild reefs should still use them, they said. For restoration, there simply aren’t many better alternatives. 

“It’s quick, it’s easy to do, people can apply it relatively straightforwardly, and it offers some kind of test,” Guest told me. “Coming up with these practical approaches makes sense.”

The sun was still low in the sky as Palumbi and I strapped on our tanks and weights and plunged into the ocean near one of Palau’s floating islands.

Sinking down felt like descending onto an alien planet. There were rolling hills of branching coral and stacks of plate coral the size of merry-go-rounds. Schools of colorful fish flew over them, like flocks of birds across a woodland.

Toward the end of the dive, we came across a single coral colony as large as a suburban home. The surface was lumpy and covered in what looked like large bulbous fingers. Given its size, the coral was likely at least three hundred years old.

When we were back on the boat, I asked Palumbi what he thought of the reef. “It doesn’t get better than this,” he said. 

Isn’t it arrogant to think we can recreate, or even fortify, something as complex as a coral reef? 

There could have been 200 species of coral on this one reef alone, Palumbi said, some of which may still be unknown to science. If this is what coral reefs are supposed to look like, even our best science probably can’t recreate them.

It seems like our time would be far better spent trying to prevent reefs like this from dying in the first place. “We all know that we have to solve the bigger problem,” Guest said. “If we don’t reduce carbon emissions and we don’t deal with climate change, nothing we do is going to help corals.”

But the way Guest and other scientists see it, restoration — and the science to improve it — is not about recreating thriving coral reefs. The goal is much more humble, and much more depressing: to prevent as many species and reefs as possible from disappearing altogether so that, if and when the planet cools back down, there’s still something left to regrow.

Reef restoration encompasses a broad range of approaches, Guest said, meant to “stop species and populations from going off into an extinction vortex.” It would seem anything that might help that cause even a little bit — including a handful of plastic picnic coolers — is worth a try.

Earlier this summer, Vox set up two big bug traps in New York City — like, literal traps that catch bugs. Our goal was to try to discover a new insect species right in the middle of the city because the bulk of them are still unknown to science. 

We now have some exciting, albeit preliminary, results to share. 

During the month of June — the only month we’ve analyzed so far — our traps captured an estimated 12,000 insect specimens, which we sent to a lab at the University of Guelph in Canada for analysis. The lab, known as the Centre for Biodiversity Genomics, pulled out specimens across three groups: scuttle flies and two kinds of wasps known as parasitoids, which lay their eggs in other insects. We’re focusing on these groups, because they’re considered “dark taxa,” meaning that most species within them are likely still undiscovered. 

That left us with just under 1,000 specimens from June to investigate further.

From there, the lab sequenced a short section of DNA from each specimen, known as a barcode. Those DNA barcodes are unique identifiers for individual organisms, and scientists use them to sort specimens. When individuals have very similar barcodes, that often means they are the same species.

Most of the barcodes from our specimens appear to be similar to barcodes of insects that scientists have already collected and sequenced. There’s a slim chance that these are members of undiscovered species. 

But there were striking exceptions: Our wasps and flies yielded more than two dozen barcode groups that are, according to a preliminary review, quite different. They are unlike anything that exists in the big genetic database, known as BOLD, which is essentially a massive library of biodiversity. That means that they may represent new species.

Now, following further analysis by taxonomists, we have a strong indication that at least a few of those barcode groups may, indeed, be new species. And this was after just one month of looking!

Before we know if we have a true discovery to announce, we want to be certain that these species are actually new. That takes hard work, for which we are leaning on Emily Hartop, an entomologist at Norway’s NTNU University Museum, and University of Guelph researchers Ranjith AP and Paul Hebert. They will verify that no one has already described the organisms matching these specimens and then publish a formal description, along with a name, in a peer-reviewed scientific journal. At that point, we’ll be able to say with more certainty that the bugs we caught here in New York City are, in fact, new to science. 

In the meantime, the traps remain open, and the freezer in my apartment will continue — to my husband’s disgust — filling up with ethanol-soaked bugs. 

You can find more information about Vox’s quest to discover a new species here.

The greatest threat to animals in the US and globally is the destruction of their habitat — replacing grasslands with farms, cutting forests for timber, building suburbs atop wetlands. It’s the main reason why hundreds of species have been listed under the Endangered Species Act, which gives federal protection to species that are currently at risk of extinction or are about to be. 

That’s what makes a recent move by the Trump administration both confusing and — according to many environmental advocates — incredibly alarming. 

In a rule published earlier this month, the administration determined that, in many cases, destroying the habitat of federally threatened and endangered species is no longer explicitly illegal, even if doing so could ultimately drive them extinct. The rule upends half a century of regulatory precedent that survived many Republican administrations. Environmental advocates also say it runs counter to the very intent of the Endangered Species Act, which Congress passed in 1973 with near-unanimous bipartisan support (and which Richard Nixon signed into law).

While the Trump administration has made several recent decisions that weaken protections for endangered species — amid what many scientists call an extinction crisis — this one may have the most far-ranging consequences. Here’s why. 

A rule that could blow up the ESA

The Endangered Species Act is a complicated law, but on a simple level it makes it illegal for anyone to “take” endangered species without authorization from the government. “Take” is defined in the law by 10 different terms: harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect.

It’s the meaning of one of those words — harm — that matters most here. Up until the recent rule, the government’s definition for harm included destroying an animal’s habitat if it impairs essential behaviors, such as breeding. That might include, say, building a hotel on top of a beach that endangered sea turtles use for nesting. Such a definition was important because destroying the habitat of an already imperiled species could push it over the edge, wildlife advocates say. What’s more is that, according to the language of the law itself, the purpose of the ESA includes conserving “ecosystems upon which endangered species and threatened species depend.”

The Trump administration, however, just threw out that definition of harm and the unambiguous protection it has long afforded habitat. And while it didn’t offer a new definition, the administration said that it agrees with a much narrower interpretation of the term — articulated three decades ago in a dissent by the late conservative Justice Antonin Scalia — that only includes actions that directly and intentionally harm individual animals, such as capturing a sea turtle to eat or keep as a pet.

“For years, federal agencies abused the ESA to obstruct lawful land use and burden American families and businesses,” Doug Burgum, Secretary of the Interior Department, which oversees endangered species protections, said in a statement. “That approach turned routine activity into a regulatory trap, drove up costs that impacted people’s lives, and expanded federal authority beyond what Congress intended. This action restores common sense, respects private property, provides much-needed certainty for landowners and follows the statute Congress actually passed.” (The Interior Department declined to provide a comment on our reporting, pointing us instead to its press release and the notice in the Federal Register.) 

Under the new rule, set to take effect in September, “harm” no longer explicitly includes actions that may accidentally or indirectly doom a wildlife population to extinction. A company building luxury villas on a private beach that endangered sea turtles need for survival would not unambiguously be considered take — and thus be illegal — unless the company knew it’d crush turtle eggs or the turtles themselves in the process. Neither would logging old-growth forests that endangered birds inhabit, building wind turbines that are known to kill endangered bats, or constructing a road that would likely get endangered snakes run over. 

The administration’s interpretation of take “really completely blows up the Endangered Species Act,” said J.B. Ruhl, a lawyer at Vanderbilt University and a leading expert on the ESA.

To be clear, these sorts of actions were never forbidden outright — and this is key. An important feature of the ESA is that, with some exceptions, it allows companies, counties and states, and federal agencies to kill or harm endangered species, as long as they take steps to limit their impact. Indeed, nonfederal organizations of all kinds have, for decades, received federal permits that allow them to “take” endangered species, in exchange for coming up with a plan to minimize the harm they may cause. In Hawaii, for example, an electric utility that operates power lines that can injure endangered birds takes steps to prevent collisions and funds an avian rehab facility that helps offset some of its impacts. 

The problem now is that these conservation plans — which wildlife advocates say are critical for species recovery — are rooted in the defunct definition of harm, according to Daniel Rohlf, a law professor at Lewis & Clark Law School. 

The whole purpose of these so-called Habitat Conservation Plans is to lessen the incidental, or accidental, impacts on endangered species, while at the same time allowing companies to still build and operate legally. But in rescinding the former definition of harm, the Trump administration has essentially just said that all that incidental killing is no longer illegal anyway. That may undermine future Habitat Conservation Plans and those that have yet to be finalized. This “pulls the rug out from under literally decades of work,” Rohlf said of the recent rule. 

Next up: The Supreme Court?

Even under the new rule, the ESA still has some important protections for habitat. When the government lists a species as threatened or endangered, for example, it usually designates what’s called “critical habitat” — areas that it deems essential to the survival of the species. Under the ESA, all federal agencies have to ensure that their actions, such as permitting new mines or wind farms, do not destroy critical habitat or jeopardize the existence of a species. Those responsibilities are still intact. 

It’s also not certain that the new rule will stick. Several environmental groups have already sued the administration to try to reinstate the former definition, alleging, among other claims, that rescinding the definition of harm violates the language and the intent of the ESA. This challenge is likely to reach the Supreme Court, Ruhl says. 

To understand what could happen next requires some important context.

Until two years ago, courts typically deferred to federal agencies to determine how to interpret ambiguous language in laws like the ESA. This legal principle was known as the Chevron doctrine. It was the Fish and Wildlife Service, for example, that published a rule decades ago clarifying that the ambiguous word harm includes destroying an endangered animal’s habitat. That interpretation survived a famous 1995 Supreme Court case, Babbitt v. Sweet Home Chapter of Communities for a Great Oregon, in which Oregon landowners and the timber industry argued that the government defined “harm” too broadly. The court decided that an “ordinary understanding” of that term “naturally encompasses habitat modification” that injures or kills endangered species.

In the summer of 2024, however, the Chevron doctrine was overturned. That means the power to interpret unclear language in laws now rests with the courts. 

The Trump administration has seized on this fact, Rohlf said. Instead of redefining what harm means, the administration simply axed the existing definition that included impacts to habitat that injure wildlife. It will now be up to the courts to decide what is considered harm in future cases brought under the ESA — such as if, say, an environmental group sues a developer, claiming that it destroyed essential habitat for an endangered species in violation of the Act. The administration did not stop short of making clear what it thinks: In the preamble to the rule, it said harm should only include actions made directly and intentionally against endangered organisms.

Wildlife advocates point out that the Supreme Court already determined that a definition of harm including habitat destruction is reasonable. That’s what Babbitt v. Sweet Home was about. But because that case rested, in part, on the now-overturned Chevron doctrine, the courts — and perhaps eventually the Supreme Court — may relitigate the meaning of harm. (The Supreme Court did make it clear that it won’t call into question decisions that relied on the Chevron doctrine before it was overturned.) 

Ultimately, it’s hard to argue that harming an endangered species, in a plain reading of the word, does not include destroying vital habitat that it needs to survive or other actions that kill or injure them indirectly, legal scholars told me. It’s also clear that Congress saw it this way when it wrote the law. There’s a whole section of the ESA about granting permits for “incidental take,” which could include damaging an animal’s habitat, according to Holly Doremus, a law professor at the University of California, Berkeley. That section only makes sense, she says, if you’re interpreting harm to include actions that accidentally and indirectly kill or injure species — which is far broader than the definition that the Trump administration would like to use.   

For the Trump administration to really get what it wants, Doremus said, it would need to remove the word “harm” from the ESA altogether. Short of that, she said, Trump officials “want to make ‘harm’ as ineffective a statutory term as possible.”

Should the administration succeed — should the courts determine that “harm” does not apply to destroying the habitat of endangered species — environmental advocates warn that the ESA will lose much of its extinction-preventing power.

“If this decision is allowed to stand, it eviscerates the statute on which imperiled species conservation has rested in this country since 1973,” said Jane Davenport, a senior attorney at Defenders of Wildlife, an advocacy group. “This is truly a stake through the heart of the ESA.”

BIRMINGHAM, Alabama — On a sweltering afternoon in June, I stood in what was essentially a roadside ditch. Sandwiched between a four-lane highway and the parking lot of a faith-based recreation center near Birmingham, the ditch was filled with cool, flowing water, a bit of trash, and, apparently, some highly endangered fish. 

Jeffrey Drummond, a biologist at the US Fish and Wildlife Service, stretched out a sheet of netting held between two poles, while his colleague kicked water into it.  

After a minute or so, we looked inside the netting. There were clumps of leaves and twigs, a few black salamanders, and a crayfish with its pincers held up, ready to fight. The biologists unceremoniously tossed them aside. They were more interested in a handful of fish that were wiggling around in the netting, each no larger than a pinky finger. 

Chris Haynes, a state fisheries biologist, popped the small fish into a container of clear water, revealing their colors: bright reds and muted shades of orange, blue, and yellow. 

“We got all three!” said Drummond, who had a beard and tattoos on his arms.

The fish were darters — slender, freshwater fish, known for their vibrant colors. And in that one go, the biologists had caught all three species that reside here: the watercress, rush, and vermilion darters. Each one is federally endangered, the strongest form of protection afforded to species in the US. 

Alabama is well known for college football, Southern hospitality, and conservative politics. But as I learned over a recent week in June, it’s also an epic biodiversity hotspot, especially in the aquatic realm. Remarkably, Alabama — which has more than 130,000 miles of rivers and streams — is home to more species of turtles, freshwater fish, snails, crayfish, and freshwater mussels than any other state in the country.  

It’s an unexpected epicenter of endangered species, too — those that are at risk of extinction and listed under the Endangered Species Act. According to a Vox analysis of government data, Alabama has more federally endangered and threatened animal species than any other state aside from California, which is three times larger by area. Endangered species are so common here that you can find them in a ditch on the side of the road.

This, of course, is an unwanted distinction. What makes it even more problematic, however, is that Alabama doesn’t have enough money to help these animals that are most at risk. 

Alabama is an extreme example of a challenge facing many US states: Much of the funding available to protect wild animals is not based on how threatened those species are. Funding streams, instead, prioritize species that people hunt or fish, known as game, and those that live in the most populous and largest states. 

This is an acute issue in places like Alabama that are not especially large or populous but full of imperiled species. And while those animals are vital to the state’s rivers and recreation industry, they also tend to be small, out of sight, and generally short on charisma — unlike, say, wolves, panthers, or whales. That makes projects to help them an even harder sell for limited environmental dollars.

That’s to say nothing of the state’s politics. Alabama is one of the country’s most conservative states, and Republicans have earned a reputation for opposing environmental protections. In 2022, the state’s Republican US congressional representatives all voted against a nonpartisan bill that would have likely quintupled funding for Alabama’s non-game species — like the endangered darters I saw in the roadside stream — had it not stalled out before passing the Senate. Some of the state’s congressional Republicans have also thrown support behind projects that may endanger even more species.

While a close look at Alabama reveals that wildlife support systems are biased against certain species and regions, it also highlights the immense power that a dedicated few human champions can have. During my trip, I met scientists who are working hard to help the state’s obscure endangered species, from mussels to snails, with whatever resources they can cobble together. They convinced me that these animals are, in fact, quite charismatic. And why, no matter our political tilts, we should rally to keep them here on Earth.

A good rule of thumb is that if you come across a refrigerator while visiting a biology lab, you should look inside of it. This rule served me well at the Alabama Aquatic Biodiversity Center (AABC), a state-run facility about an hour from Tuscaloosa. In two fridges I found plastic containers full of pregnant freshwater mussels. 

AABC is primarily a nursery for endangered mussels. A collection of several old buildings just off a rural highway, the facility collects pregnant adults, raises their babies, and then releases them months later in streams to help restore their wild populations. 

Mussels are essentially nature’s Brita filters. A single large mussel can filter as much as a liter of water an hour, removing bacteria, algae, and other potentially harmful particles, said Carla Atkinson, a mussel researcher at the University of Alabama. And a healthy stream can have 50 mussels in a single pillow-size patch, she said. Abundant mussel populations can save cities money on water filtration and make rivers more swimmable for people and more habitable for other species. 

Alabama used to have more than 180 species of freshwater mussels, says Paul Johnson, a state biologist who runs AABC. Two dozen of them have already gone extinct, he said. Close to 70 of those that remain are federally endangered or threatened, largely as a result of dams and water pollution, and AABC is currently working to restore about 15 of them.

You might think raising animals that resemble rocks is easy, but it very much is not. And the reason why is best explained by what is, without question, the most exciting thing to know about these animals. 

Mussels have a “foot” that helps them burrow, but they can’t easily travel. That makes it hard for them to colonize new habitats and, in turn, survive changing environmental conditions. But over millions of years, they evolved a hack: They hitch a ride on fish. Or rather, their babies do. Larval mussels, known as glochidia, spend their first few weeks of life attached to the gills of fish, before dropping off elsewhere in the riverbed to begin a largely sedentary lifestyle in a new place. 

The real ingenuity is in how those glochidia get onto fish in the first place. Essentially, mussels pretend to be fish food to lure them in. Some females wave around a fleshy part of their body so it looks like a swimming minnow. Others release into the water packets of glochidia that have evolved to look like insect larvae. When fish go in for a bite, they get a face full of baby mussels that soon after attach to their gills, like real-life xenomorphs.  

These lures are surprisingly convincing. One of the species found here, known as the Southern pocketbook mussel, for example, uses its fleshy mantle to mimic a bait fish.

Meanwhile, a federally threatened Alabama mussel, the orangenacre mucket, clumps its glochidia together in two fish-shaped masses, which it tethers to its body with a mucous strand. This creates the illusion of free swimming fish. When a fish bites the lure, the clump ruptures and the babies get sucked into the fish’s mouth and over its gills. 

My favorite examples come from mussels in the genus Epioblasma, all of which are endangered. They leave their shells ajar, and produce a lure that mimics some kind of fish food, like crayfish eggs or larvae. When hungry fish poke their heads inside, the mussels snap shut like a Venus flytrap — and blast the fish in the face with babies. After this abrupt encounter, the fish are released to go on their way with their new stowaways. 

Different kinds of mussels typically rely on different “host” fish. And that brings us back to one of the challenges of running a mussel nursery; not only do you need pregnant mussels, you also need lots of fish. 

To rear these mussels in captivity, scientists first find and collect pregnant, or “gravid,” mussels from the wild and store them in refrigerators. The cold keeps the animals pregnant for longer. Then they extract the glochidia manually and add them to a container with the proper host fish. Those fish get “infected” in a matter of minutes, at which point the fish are moved into tanks in a nearby room. Weeks later, nearly invisible mussels drop off the fish and fall to the bottom of those tanks, where they’re collected by scientists. From there, the young mussels grow in plastic buckets indoors and, once they’re a bit bigger, in plastic buckets outdoors — in a nearby well-fed pond.    

I visited the pond one sunny afternoon with Johnson, who wore a ball cap and glasses. Johnson is self-deprecating and often finishes his sentences with a bout of disarming, wheezy laughter. A Kentucky native with an accent to match, he’s been working with endangered species for more than 30 years. 

A wooden dock fitted with pipes and tubes extended out onto the pond. Submerged in the clear water around it were about 80 weighted buckets full of mussels. The tubes, I learned, move air through the lids of the buckets and — thanks to some confusing physics — help cycle water through them, mimicking a stream. It looked and sounded like the water around the dock was boiling.

Johnson pulled one of the buckets onto the dock. Inside was what looked like hundreds of pumpkin seeds, golden and glossy as if they’d been dipped in caramel. These were baby pale lilliputs, a federally endangered mussel species, so named for its small size; they’re about an inch and a half long when fully grown. 

Lilliputs are native to rivers of Alabama and Tennessee, but they nearly went extinct in the mid-1900s, as the US government turned rivers into channels, farmland spread, and cities and suburbs expanded. “There are more of these in this bucket than there are in museum collections around the world,” Johnson said, to emphasize how rare they are. 

Michael Buntin, a state biologist at AABC, pulled up another bucket. This one was filled with hundreds of two slightly larger species: the Alabama rainbow and Coosa moccasinshell. “That is absolutely one of the rarest species in the United States,” Johnson said of the moccasinshell, which was pointy and brown. I had now seen more moccasinshell mussels than all but a handful of people in the world, Buntin told me.

You might imagine that a facility managing hundreds of some of the nation’s most endangered species would have state-of-the-art technology, a large team, advanced security, and a carefully orchestrated media presence. AABC has none of those things. Most of the technology is DIY — Tupperware containers in refrigerators, plastic buckets with holes cut into them. AABC has only four full-time employees. The buildings are old and falling apart. “It’s low budget,” Buntin said with a snicker. 

“We have the most species and the fewest dollars.”

Paul Johnson

That’s partly out of choice, Johnson said. Simple, homemade systems are easier to fix if they break. But it’s also because the facility — like so many state conservation efforts across the country — is wildly underfunded for the number of species it is charged with bringing back from the brink of extinction. 

“We have the most species and the fewest dollars,” Johnson said of Alabama, adding, sarcastically: “That makes a lot of sense.”

The headwinds facing efforts like this begin far upstream. Most funding for state wildlife agencies — which oversee the bulk of the country’s conservation, including endangered and threatened species — actually comes from selling hunting and fishing licenses, along with federal excise taxes on guns, ammo, and fishing gear. 

This setup not only encourages states to promote gun use but also to spend those funds on managing animals that people like to hunt and fish. In fact, some of that money is legally restricted to programs that support birds, mammals, and sport fish. And that, of course, does not include many of the nation’s endangered species — including most of those in Alabama. 

Just look at the roughly $450 million annual budget for the Alabama Department of Conservation and Natural Resources, which manages parks, hunting, and conservation. Of that, only about 1 percent goes toward helping non-game species, including mussels, crayfish, snails, and many endangered fish, according to Amy Silvano, who leads non-game efforts at the department. AABC is a key part of the agency’s non-game division and receives a total average annual budget of just $750,000, Silvano said. 

While funding for non-game species is a challenge nationwide, Alabama is, in some ways, also uniquely ill-positioned.

Alabama has a human population of about 5 million, and it ranks in the bottom half of all US states by area. That matters, because much of the limited federal money that is made available for at-risk animal species is allocated based on a state’s geographic size and human population — not on how many endangered or threatened species it has. Larger and more populous states like New York and Illinois receive more funding to protect endangered species than Alabama does. Even though they have far fewer of them. 

“The states with the greatest biodiversity challenges aren’t necessarily the states receiving funding proportional to those challenges,” said Michelle Lute, executive director of the advocacy group Wildlife for All.

These problems are not unfixable. A few years ago, the US House voted on Recovering America’s Wildlife Act, which would have dispersed $1.3 billion across all US states to protect their imperiled species, including some $25 million for Alabama. Though Republicans from Alabama voted against it, the bill passed the House and was widely considered nonpartisan. It later stalled in the Senate and has yet to become law — because lawmakers couldn’t agree on how to pay for it.

Alabama has actually had more success in boosting funding for threatened species at the state level. The Republican-dominated state legislature recently approved $2 million for the state’s threatened species from its general fund. Some of that money is going toward fixing up aging infrastructure at AABC. 

Chris Oberholster helped lobby for those state funds while he was working in external affairs for The Nature Conservancy, a large environmental nonprofit. Oberholster, now director of philanthropy at another green group, said one key to garnering support for conservation in Alabama has been framing it as a boon for outdoor recreation, such as by maintaining the natural beauty of lakes and streams through restoring mussels. 

Preserving the state’s unique ecological heritage has also been a selling point for conservation, he said — many of these aquatic species are found only in Alabama, and that makes people want to help save them. 

If there’s a lesson here, it is perhaps an obvious one: You can find support, and even cash, for wildlife conservation everywhere, as long as you connect the benefits of that work to the values of people in the local community. 

On another muggy afternoon, I joined Atkinson, the University of Alabama researcher, in a shallow stream east of Tuscaloosa. She shuffled around, careful with each step, holding in her hands what looked like a metal detector — a pole connected to a ring-shaped base, which she kept submerged underwater. 

Atkinson wasn’t searching for metallic treasures but biological ones. She was looking for very rare mussels.

A mussel evangelist who often works with AABC, Atkinson was searching with Johnson for Coosa moccasinshells that had been released here in recent years. Scientists “chipped” several of them before releasing them in the river, which means the mussels were fitted with a microchip, not unlike a pet dog or cat. The device that Atkinson was carrying, known as a PIT-tag reader, helps locate those chips, making it easier for researchers to monitor rare mussel populations.

Despite its resource constraints, AABC has released roughly 300,000 mussels across more than a dozen species in Alabama’s rivers over the last 15 years. Some reintroduced populations are now breeding on their own, Johnson said. In fact, AABC has been successful enough in raising and releasing one particular species — the pale lilliput, the ones that look like golden pumpkin seeds — that it may soon be eligible for delisting under the Endangered Species Act, meaning it would no longer be considered endangered. 

Two other species are on their way to getting off the list, too, Johnson said, largely owing to AABC’s restoration work. With more resources the center could do more, said Johnson, who suggested they would likely restore more mussels and other aquatic species too, including fish and crayfish. “We can expand what we’re doing pretty easily,” Johnson said.

After several minutes canvassing the streambed with the PIT-tag reader, Atkinson got a ping. A Coosa moccasinshell was, apparently, right by her feet. 

I thought she’d simply reach into the water and grab the thing. She had no such luck. Not only do mussels look like every other rock on the bottom, but they can also burrow into the riverbed, making them hard to find, even with a literal mussel detector. 

Atkinson threw on a mask and snorkel and plunged her head underwater. A few minutes later, she popped up, smiling, with a shiny brown lump in her hand.  

“It’s gratifying to see that they’re still persisting and that we chose the right habitat,” said Johnson, who had been busy collecting pea-size snails to show me. 

I’ll be the first to admit that this creature, as it appeared before me, was not so thrilling to look at. It was not cute or colorful. And aside from an almost imperceptible movement of its shell, it offered little proof of life. 

Then I thought about what this one animal does. How it thoughtlessly filters the water just by existing, making it livable for everything else, at no cost to us. How it mimics fish food, despite having no brain or true eyes, a trick forged by millions of years of evolution. How it can help stabilize the riverbed and minimize erosion by anchoring itself to the bottom.

The abundant wildlife in Alabama might not be charismatic in a traditional sense, but there’s an understated impressiveness to it. The fish in the ditch by the highway evolved to live in isolated springs and are still persisting, if barely, in the middle of a sprawling city that sprung up around them. Some crayfish — there are about 100 species in Alabama, many of which are imperiled — appear to engineer ventilation systems that bring fresh air into their underground burrows. 

Before leaving Alabama, I drove south to a bog about 45 minutes from Mobile. It was spectacular. The ground was blanketed by carnivorous pitcher plants and crayfish burrows. The crayfish here are “primary burrowers,” Brian Helms, a researcher who studies these animals at Alabama’s Troy University, told me, as we walked through the bog. Although they breathe with gills, like fish, they live on land, he said. They just dig down deep enough to reach the water table. 

It’s spots like this that represent the unique environmental heritage that Oberholster was talking about. Though often hidden, they have real value. And if more people, and especially lawmakers, don’t see that, the animals within them may not be around for much longer.

Melissa Hirsch contributed reporting.