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Welcome to the extinction capital of the world

Our planet faces a mass extinction. I visited ground zero.

Five small snails with brown and white spiraled shells in a clear petri dish next to a leaf.
A handful of federally endangered Hawaiian snails called Achatinella fulgens.
Benji Jones is a senior environmental reporter at Vox, covering biodiversity loss and climate change. Before joining Vox, he was a senior energy reporter at Insider. Benji previously worked as a wildlife researcher.

PEARL CITY, Oahu — On a warm November afternoon in a trailer not far from Pearl Harbor, a scientist named David Sischo popped open the lid to a small plastic tank. From a jumble of leaves, he pulled out something precious.

“I would argue that they’re one of the rarest animals on Earth,” Sischo said.

A hand wearing a blue latex glove holds a clear plastic petri dish with five small cream and brown striped snails above a box containing green vegetation.
David Sischo holds a petri dish with a handful of Achatinella fulgens snails.

In his hands were several cream-colored snails. They had thin brown bands circling their shells, like swirls of caramel in a small scoop of ice cream.

The snails were asleep and tucked into their shells as Sischo placed them on a petri dish (snails are nocturnal). But after a few minutes, their antennae popped out, their gooey feet emerged, and they started to move. Slowly.

These snails, a species called Achatinella fulgens, are one step away from extinction. They exist only in this room, a lab run by the state’s Snail Extinction Prevention Program (SEPP). Funded in part by the Endangered Species Act (ESA), it’s a modern-day Noah’s ark, home to roughly 40 species of snails that are either extinct in the wild or about to be.

In recent decades, hundreds of species of snails have gone extinct across the Hawaiian Islands, said Sischo, a state biologist who runs SEPP. Another hundred are now at risk of blinking out. These animals may lack charisma by some definitions, but they are revered in native Hawaiian culture and linchpins in their ecosystems. They recycle nutrients, helping fertilize the forest, a source of water for the island.

“If we lose snails, we’re probably screwed,” said Ken Hayes, a snail researcher at Bishop Museum, a natural and cultural history museum in Honolulu.

A small brown and white snail rests on a brown leaf held by a blue gloved hand.
Another federally endangered snail, Achatinella fuscobasis. Scientists believe that it’s extinct in the wild.
A small snail with a brown and cream striped shell sits on a fern leaf.
A tree snail called Partulina perdix. It’s very rare in the wild, though it’s not listed under the Endangered Species Act.

This fight for survival is not unique to snails.

Scores of native Hawaiian species have been disappearing in recent decades, including many plants, birds, and insects. In October, the US Fish and Wildlife Service formally declared 21 species extinct nationwide. Eight of them were Hawaiian birds. There is an extinction crisis playing out worldwide — where as many as 1 million species are creeping toward the edge of existence — but the state of Hawaii is ground zero. It has lost more species than any other state, which is one reason why it’s been dubbed the extinction capital of the world.

Snails and birds in Hawaii, and imperiled species across the nation, are not without a lifeline. Many of them — including Achatinella fulgens — are classified as federally threatened or endangered. That means they’re protected under the Endangered Species Act, a federal law that grants them the highest level of protection afforded to wildlife in the US. There are some 1,670 species and subspecies protected by the Act, according to a Vox analysis of federal data (the number includes some populations within species). Nearly a third of them are found in Hawaii.

Now on the cusp of its 50th year, the Act is widely considered to be the nation’s strongest environmental law. Yet many of the species it aims to protect, and the ecosystems they call home, are struggling to hold on. The law faces more complex challenges today than it did when Congress passed it in 1973, including the threat of climate change. This raises the question: Is it still up for the job?

There’s no better place to explore this question than in Hawaii.

Photo taken on a bluff that overlooks the ocean below. In the distance, a white lighthouse tower is visible.
A historic lighthouse on the north shore of Kauai in Kīlauea Point National Wildlife Refuge.

Those snails in Sischo’s lab were once so common on Oahu that Native Hawaiians would use them to make leis, traditional garlands that symbolize love and respect. But by 2012, when Sischo started working for the state, researchers could find just one population in the wild. A couple dozen or so of the snails were glued to the leaves of guava trees in a ravine just uphill from the popular beaches of Honolulu.

Their future darkened from here. A landslide in the mountains knocked a number of snail-bearing trees down into the ravine. And in the aftermath, Sischo’s team could find only six snails left. They eventually brought those snails into captivity and grew the population to 50 before a pathogen swept through the lab, collapsing it down to fewer than 10. “It was a nightmare,” Sischo told me.

Today, the captive population of Achatinella fulgens is back up to roughly 60, hanging on in a purgatory-like existence. Sischo keeps the adults in separate tanks so they can’t spread disease to each other. “We’ll keep them in solitary confinement, and then they’ll get conjugal visits periodically,” he said.

A drawer full of native Hawaiian snail shells at the Bishop Museum in Honolulu.

The Endangered Species Act is a complex law but its goal is simple: to restore populations of imperiled plants and animals, and the ecosystems they rely on, so that they don’t go extinct. Among other provisions, the law makes it a federal crime to harm species that are classified as endangered, meaning they’re at risk of extinction, with a few exceptions. It also funds projects to conserve those endangered species, such as Sischo’s work to save Achatinella fulgens.

If you look at the Endangered Species Act narrowly — as a means to prevent extinction of some of the nation’s rarest species — it’s a powerful law. More than 99 percent of plants and animals on the federal endangered species list are still on this planet.

A gray seal sleeps on the sand by the ocean.
People stand on the beach and observe a group of sea turtles resting on the sand.
A dark gray whale’s fin and back are visible above the surface of the ocean.
Two white birds with light blue beaks. One rests on the branch of a bush. The other is pictured mid-flight.

Top left: An endangered Hawaiian monk seal snoozing on the beach on the north shore of Kauai. Top right: Green sea turtles, a federally threatened species, on a beach in Kauai, where they come ashore — often by the dozens — to rest. Bottom left: A short-finned pilot whale, off the coast of Hawaii (photo taken under the authority of NMFS MMPA/ESA Permit No. 26596). Bottom right: Red-footed boobies in Kīlauea Point National Wildlife Refuge.

Yet the Act is no match for the collapse of ecosystems at large or the growing threats that shrink populations in the first place. Climate change is altering habitats and has helped spread invasive species. Cities have swelled, as has plastic pollution. Scientists have documented widespread losses within groups of animals like birds and bumblebees. More than 40 percent of ecosystems in the US are now at risk of “range-wide collapse.” The Act is helping a subset of species hang on, while the rest of nature is in decline.

These declines are especially extreme in Hawaii.

For millions of years, plants, birds, and other creatures evolved in isolation on the Hawaiian islands, in the absence of certain predators and parasites. There were no mosquitos, no grazers. Plants didn’t need to defend themselves, so they mostly lack thorns or spines; a mint plant in Hawaii produces no mint flavor— a “mintless” mint — because it doesn’t have the chemical that such plants use to repel herbivores.

A black cat with a white spot on its chest sits on pavement.
A feral house cat near an abandoned building on Hawaii (the Big Island). Conservation scientists consider cats to be a major threat to native birds.
A gray cat lies down on gravelly pavement.
Feral cats are abundant on Hawaii.

Then settlers arrived — first the Polynesians and then, starting in the late 1700s, the Europeans. People, and especially Europeans, brought with them a hodgepodge of foreign plants and animals, such as pigs, cats, and rats, against which native species were largely defenseless.

For Achatinella fulgens, a major problem was the cannibalistic rosy wolfsnail. The state first introduced the mollusk to the islands in the 1950s as a means to get rid of yet another nonnative snail. The wolfsnail is a skilled predator that hunts its native cousins by tracking their trails of slime.

Climate change has only given animals here more to contend with.

Rising temperatures are helping spread certain invasive species uphill, including mosquitos that kill birds and perhaps even the wolfsnail. Heat is also damaging coral reefs. Sea level rise, meanwhile, is shrinking coastal habitats where seals, turtles, and other animals nest. It’s mucking everything up.

In some ways, the geography and history of Hawaii make the state uniquely vulnerable to environmental threats. Yet the problems it faces are increasingly universal, providing a glimpse into what the future on Earth might look like if environmental policy fails to adequately address them.

“What I always like to say is that Hawaii is a mesocosm of what’s happening in the world,” Hayes said. “If we can understand what’s happening in this isolated environment, and we can find some solutions here, those same solutions will work in New York. We can make life better for everyone.”


One sunny morning last month, on a grassy hillside in northern Kauai, Lauren Pederson knelt next to a hole in the ground. It looked like a small chimney. Pederson, a conservation technician at an environmental group called Pacific Rim Conservation, removed a container covering the top so I could peer inside. I saw feathers in shades of gray. A black beak. Lots of fluff.

The hole was an artificial burrow home to a young seabird. The bird, known as an ua‘u, or Hawaiian petrel, possessed the awkward look of an adolescent. It was nearly ready to fledge, Pederson said. Once they leave the nest, ua‘u spend several years at sea before returning to shore to nest.

A fluffy gray bird seen from above.
A young ua‘u, or Hawaiian petrel, in an artificial burrow in the Kīlauea Point National Wildlife Refuge. The bird is part of conservation initiative called the Nihoku Ecosystem Restoration Project.

Ua‘u were once super-abundant in Hawaii, like, say, pigeons in New York. Their wings darkened the skies and their guano fertilized the soil, helping give rise to the state’s lush rainforests. As hotels and power lines shot up and predators moved in, however, seabird populations began to crash. In 1967, following fears that ua‘u might go extinct, these birds became one of the nation’s first species to be classified as endangered and granted federal protection (under a predecessor of the Endangered Species Act, called the Endangered Species Preservation Act of 1966). That designation means that the species is in danger of going extinct across at least a large portion of its range.

There’s no question that the Act has helped ua‘u in the decades since. In the aughts, a luxury hotel on Kauai’s north shore was harming endangered seabirds, according to environmental advocates. When young birds like ua‘u fly out to sea for the first time, they navigate by the moon and stars. The hotel’s bright lights were disorienting them, causing the birds to fly toward land and, in some cases, fall out of the sky from exhaustion. An environmental group called Earthjustice sued the hotel, alleging that it was violating the ESA. The hotel ultimately settled the suit and agreed to reduce light pollution and fund seabird conservation.

A fence whose posts are connected by a mesh-like netting bisects a grassy hill.
A fence at the Kīlauea Point National Wildlife Refuge that’s designed to keep predators like rats and feral cats out.

Funding from this settlement, among other sources, helped establish a colony of ua‘u and a‘o — another seabird, known as the Newell’s shearwater, which is federally threatened — in Kīlauea Point National Wildlife Refuge. That’s where I saw the fluffy fledgling that morning in November. Part of the refuge was fenced in and cleared of predators. Dozens of artificial burrows were installed. And then, beginning in 2015, a number of ua‘u and a‘o were brought here from other colonies on the island — including the parents of the chick I saw. The colony is small, but birds are coming back to raise their families.

“We’ve been able to use the law to force people who are harming these birds to invest in projects to protect their nesting colonies,” said David Henkin, a senior attorney at Earthjustice, who’s based in Honolulu. “[The ESA] is a heavy hammer that can get some good things done.”

ESA lawsuits, or the threat of them, have helped fund a range of conservation efforts across the islands. To offset harm that power lines in Kauai cause endangered seabirds, for example, the local electric utility in Kauai puts money toward a number of projects including an avian rehab center called Save Our Shearwaters. The center provides health care for native seabirds like ua‘u and a‘o that sometimes run into power lines.

A black bird underwater, seen from above.
A seabird called an a‘o, or Newell’s shearwater, dives in a small swimming pool at Save Our Shearwaters, a seabird rehab center in Kauai.

The next day, at a quiet beach on the east shore of Kauai, I met the center’s rehab manager, Jacqueline Nelson, who had some blue boxes with her. Nelson opened one and, using a towel, pulled out a bird with a black coat and white underbelly. It was a young a‘o that had come into the facility the day before with dirty plumage, a sign that it had fallen to the ground.

The bird was now clean and ready to try flying again. Nelson delicately placed it on top of a boulder. The a‘o sat there for a minute and looked around, seemingly confused by what it should do next. But then it stretched out its wings and oriented itself toward the ocean — and jumped.

A bird with black wings and a white belly and neck  sits on a rock.
A young a’o that was rehabbed at Save Our Shearwaters prepares to take flight.
A bird with wings outstretched flies through a blue sky.
The bird flew out to sea, cruising just above the waves, until it disappeared from sight.

The Endangered Species Act has, in a literal sense, given these birds flight. The number of a‘o and ua‘u appears to be stabilizing — albeit at a low number — according to André Raine, a seabird expert and science director at the ecological consulting firm Archipelago Research and Conservation. “Things are looking better for them now, but it is literally only because the funding is available to protect them,” said Raine, who’s also involved in seabird conservation funded in part by the electric utility.

And to be clear: There are plenty of examples of the Act helping conserve plants and animals in Hawaii and across the country. When I visited the islands in November, endangered Hawaiian monk seals and threatened green sea turtles were abundant enough that I would stumble upon them on the beach. Both species, thanks to work funded by the ESA, have shown signs of recovery in recent years. To date, the Act has restored populations of more than 60 species in the US to the point where they no longer need federal protection.

A white and brown bird  with a black head and beak stands in the grass.
A nēnē, Hawaii’s state bird and a federally threatened species, near farmland in Kauai.

“What I’m absolutely certain of is that if this country did not have an Endangered Species Act, hundreds of the species that exist today would not be here,” said Jamie Rappaport Clark, former director of the Fish and Wildlife Service, which oversees the Act, and CEO of the environmental group Defenders of Wildlife.


I am not a birder. I am also partially colorblind. This made the task before me one morning last month particularly challenging: searching for some of Kauai’s rarest forest birds.

The mountains of Kauai were once teeming with native birds that filled the forest with sound and color. Hikers could hear the calls of the Kauai ‘akialoa and the nuku pu‘u, olivine birds with long, curved bills. They might glimpse the Kauai ‘ō‘ō, a small black bird with yellow patches on its legs, or the brown and gray kāma‘o, which was known to sing loudly as it shot up through the trees before dropping down below the canopy.

All of these forest birds, among many others, are now extinct.

Like many of the state’s snails, forest birds here have been utterly ravaged by nonnative species. Not only do rats and cats eat their chicks and steal their eggs, but a bite from a nonnative mosquito can infect them with avian malaria, and it’s often fatal. Since the late 1700s, when European colonization began, nearly half of the state’s 73 native bird species and subspecies found nowhere else on the planet have disappeared.

“We have a relationship to these birds,” said Sabra Kauka, who teaches Hawaiian studies and Hula at a school in Kauai. “To see them disappear is like watching a relative pass. It makes me cry,” said Kauka, who also works with the state department of education.

A group of small taxidermy birds each tagged by the feet with handwritten labels.
A collection of Hawaii elepaio, a native flycatcher, at the Bishop Museum.

In more recent decades, rising temperatures have helped spread malaria-ridden mosquitoes to higher elevations. Regions that were once too cold for these bloodsuckers — and thus safe havens for birds — have been warming up, putting the forest’s remaining native species at an even greater risk as more mosquitos move in.

Avian species in a group called honeycreepers are especially vulnerable to malaria, including the federally endangered ‘akikiki, a small bird with gray and white plumage. There are fewer than a dozen of them left in the wild, according to Lisa (“Cali”) Crampton, an avian ecologist who leads the Kauai Forest Birds Recovery Project (KFBRP).

“We believe that most of the ‘akikiki have died,” Crampton said. “They are functionally extinct in the wild,” she added, meaning there are fewer than 10 breeding females. Other native species like the ‘akeke‘e, puaiohi, and ‘anianiau — some of which are listed as federally endangered — are also now rare in Kauai and at risk of vanishing.

Still, on that morning last month, I hoped I might find one. Or more realistically, I hoped my hiking companion would find one for me.

Small taxidermy birds with handwritten labels tied to their feet with string.
Specimens of federally endangered ‘akikiki at the Bishop Museum’s ornithology collection.

It was overcast, and I was on a trail in central Kauai with Dylan Blanchard, another conservation technician at Pacific Rim Conservation. The forest was like something out of a fairy tale. Fluffy patches of green moss dotted the floor. Each tree was a world, their branches covered in a potpourri of lichens, mosses, and plants.

Yet for all the magic here, there was a noticeable void. It was quiet. Every now and then Blanchard would take a speaker out of his backpack and play the calls of native birds. They wouldn’t call back. “It’s kind of sad,” he said. “This is what it’ll eventually be: playing calls for birds that are nowhere.”

Funded in part by the Endangered Species Act, KFBRP focuses on two main approaches: breeding birds in captivity to ensure there’s a backup population should the wild one go extinct, and reducing the number of mosquitos that carry avian malaria.

The latter approach relies on a fascinating bit of biology. Most mosquitos and many other insects naturally carry a kind of bacteria called Wolbachia in their cells. Two mosquitos can only successfully breed with each other, however, if they carry the same strain of that bacteria. In Kauai, the plan is to release hundreds of thousands of male mosquitoes that are inoculated with a different strain of Wolbachia than the insects on the island (similar work is underway in Maui). If successful, the invasive mosquito population should crash.

“It’s kind of our last hope,” said Bryn Webber, who leads KFBRP’s mosquito control work. “If we don’t do this, we’re going to see the birds go extinct in front of our very eyes.”

Raising birds in captivity and controlling mosquitos will undoubtedly help the island’s imperiled birds hold on; it will help stave off extinction, the worst-case scenario. Yet it’s hard to see efforts like this as sustainable, as anything more than a lifeboat. Mosquito control is incredibly costly. Plus, malaria is just one of many threats facing the ‘akikiki and the other endangered forest birds. Releasing captive-bred birds can also fail.

Many of the efforts to save snails like Achatinella fulgens seem similarly narrow. Although they buy time, they typically don’t aim to heal the ecosystem that put these species at risk in the first place.

Beyond breeding snails, the state and other environmental workers have built a dozen “snail jails” in the forest: enclosures, about the size of a basketball court, designed to prevent invasive species from getting in. The perimeter is lined with low-voltage electrified wires that will shock rosy wolfsnails if they get too close.

A snail lying on a bed of leaves seen under a magnifying glass.
A native Hawaiian snail in the genus Catinella at the Bishop Museum.

These enclosures have helped, Sischo said, but they’re not enough to stop the precipitous decline of snails statewide. They do little to help free-roaming species, for example, or address the more intractable impacts of climate change, which is drying up the islands.

“I feel like right now we’re just putting Band-Aids on things,” Sischo said. “The US Fish and Wildlife Service talks about recovery as a goal for listed species. That’s not one of our goals. Our main goal is to keep them on earth. Period.”

By focusing on last-ditch efforts to save a finite number of species, the Endangered Species Act runs the risk of missing the bigger picture, of failing to understand and address the widespread unraveling of ecosystems that’s pushing countless plants and animals — federally protected or not — closer to the edge.

You can think of the endangered species list as the ICU at a hospital, said Allen Allison, a zoologist at the Bishop Museum. “While you’re concentrating on [those patients], the next tranche is headed toward the abyss,” he said. “And like in the ICU, you’re not always successful.”

A few hours into our hike in Kauai, Blanchard and I stopped for lunch in a flat grove of ‘Ōhi‘a trees. It was here, he said, that he had seen an ‘akikiki several months ago.

I sat on the damp forest floor and craned my head toward the canopy. Then I heard a sound that jolted me to my feet — a shrill cheep that sounded like the ‘akikiki recordings I had been listening to. We scanned the forest branches as the bird continued to call.

Then Blanchard spotted it — not an ‘akikiki but another imperiled honeycreeper found only in Kauai called the anianiau. Through binoculars, I saw the bird, a small patch of yellow peeking through the canopy. Anianiau are not federally protected under the Endangered Species Act, but, said Crampton, they too appear to be crashing.

A man with gray hair and glasses looks down at a drawer of taxidermy yellow and green birds.
Allen Allison looks at a drawer full of ’anianiau at Bishop Museum’s ornithology collection.

None of the 20-plus experts I spoke to for this story want to throw out the Endangered Species Act. But it could be a lot better, they said.

At a minimum, the Fish and Wildlife Service (FWS), the federal agency that oversees the majority of listed species, needs a lot more money to do its job. “Currently, the Service only receives around 50 percent of the funding required to properly implement the Act,” more than 120 conservation groups wrote in a letter to Congress in March. “Conserving our planet’s natural heritage is a monumental challenge, but we can do more.”

A bigger budget could help FWS classify additional species as threatened or endangered — i.e., build more lifeboats — and do so more quickly. It could also mean more money to help populations recover, some of which is funneled into efforts like KFBRP and SEPP.

Kīlauea Point National Wildlife Refuge.

It’s difficult to overstate the impact that more funding would have on these projects.

“For several millions of dollars, you could secure a lot of species’ existence,” said Sischo. The project needs more staff and some one-time infusions of cash to build more snail jails, he said. The 2023 budget for the Department of Defense was more than $800 billion. A tiny fraction of that — less than .01 percent — could likely prevent the extinction of some of Sischo’s snails, which would in turn bolster ecosystems and the resource security they provide.

FWS acknowledges these funding shortfalls. “The Act continues to be one of our most effective tools,” said Gary Frazer, assistant director for ecological services at FWS, which administers the ESA. But “it is certainly under-resourced,” he added, a point he says the Service has made clear in its budget request. (The Fish and Wildlife Service actually requests a cap from Congress on spending to classify species as endangered as the list grows faster than the agency is able to keep up.)

With little money to spend on a growing number of imperiled species, scientists and officials supported by the ESA are forced to triage. In the rush to save ailing life, they channel time and money toward essential actions to stop imminent extinctions instead of addressing more fundamental threats.

More troubling is that many of these threats are getting worse. In 1973, when Congress passed the ESA, “nobody said the words climate change,” Clark, the former FWS director, told me. Now, rising temperatures are escalating the risks to animals like corals and snails, “putting enormous pressure” on the law, Clark said. It’s becoming hard to imagine the ESA achieving its main goal — conserving vulnerable species — without also addressing climate change and other, more fundamental problems that are causing ecosystems to collapse.

Achatinella fulgens may yet survive. If all goes to plan, Sischo’s team will grow its population into the hundreds, one conjugal visit at a time, at which point they will start releasing them into those fortified snail jails.

The fate of the island’s many other snail species is not so clear.

Near the end of my trip, Hayes drove me to the top of the highest peak on Oahu, a sacred place called Mt. Ka‘ala. It was cold and rainy and miserable at the summit — perfect for “snailing,” said Nori Yeung, another snail researcher at the Bishop Museum who came with us.

Finding snails was a lot easier than finding birds. We walked through a misty forest along a wooden boardwalk, and every few feet Yeung would turn over a leaf with a tiny snail clinging to the underside. Some of them were no larger than a peppercorn. “They are sentinels,” Yeung said of snails. “They are letting us know about the health of the ecosystem. And we’re just losing them.”

A tiny, almost translucent, white snail with a silvery shell.
A baby snail of the species Catinella rotundata, which is in a family of snails referred to as “snot in a hat,” at the Bishop Museum.

We saw at least five different species, but my favorite was a thumb-sized snail that Yeung and Hayes affectionately referred to as either “snot in a hat” or “chonky boi.” The nicknames come from its appearance: The snail was basically a big pile of goo with a small hat-like shell.

I asked Hayes what this snail was really called. “That’s an undescribed species that is only found on Mt. Ka‘ala,” he said, meaning it doesn’t have a name. It’s in the family succinea, though it’s not yet formally known in science. In other words, if the ESA is an ark, these snails aren’t on the manifest.

This snail is the kind of animal that would benefit from a more holistic approach to conservation, Hayes said, one focused on all of biodiversity. If the Endangered Species Act doesn’t evolve, the US could lose species that it doesn’t even know exist.

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