When the Last of a Species Breathes No More
“When the last individual of a race of living beings breathes no more, another heaven and another earth must pass before such a one can be again.”
– American Naturalist William Beebe, The Bird: Its Form and Function
Illustration by Marlou Jaspers
Extinction is when the last of a species dies and the species is lost forever. The number of species on Earth goes down by one. An ember in the fire of life fades into darkness. Species have gone extinct at a fairly steady rate for hundreds of millions of years, but occasionally the extinction rate skyrockets, many life forms vanish, ecosystems collapse, and the world is changed forever. This is called a mass extinction. Five of these events have been so terrible, come so close to driving all species extinct, that they nearly ended life on Earth forever.
We are now entering the Sixth Great Extinction. This event, termed by scientists the Anthropocene Mass Extinction, is fueled entirely by humanity’s reckless and greedy assault on the living world. Threats such as habitat loss, climate change, and introduced species are putting much of life on Earth at risk of extinction. Scientists at the U.N. Convention on Biological Diversity have estimated that 150 species go extinct per day, adding up to nearly 55,000 extinctions per year and more than half a million every decade. The five great extinctions of the past were brought about by terrible natural forces from glaciation to asteroids and volcanism. But this time, warns the CBD report, the sole cause “[is] human activities.”
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Scientists are still debating when the Anthropocene, the geologic age defined by human actions, officially began. It will be denoted by wherever our signature is first recorded in the Earth’s geological sediments. The dawn of the Anthropocene Extinction Event, however, is much harder to pinpoint. My opinion is that it started in the 1980s. This period marked a turning point in human-caused extinction when we inadvertently introduced a deadly fungus—a pathogen of frogs and toads—to ecosystems around the world, resulting in the worldwide collapse of anuran species. Up until this point, humans had extinguished many isolated species and ecosystems, but the fall of the amphibians was the beginning of global trends of decline among large clades of species.
The pathogen was first noticed when frogs and toads began to suddenly disappear. Many species declined, some to extinction, within an exceedingly short timeframe. After years of research, scientists found the catalyst to be a chytrid fungus known as Batrachochytrium dendrobatidis. It infects the skin of anurans, causing severe illness and death.
Human activities rapidly spread the chytrid around the globe and the mysterious declines of the 1980s quickly became a worldwide extinction crisis. As the chytrid spread, frog and toad populations crashed at a terrifying rate. Nothing could be done to stop the panzootic and it continues to this day. Chytrid, in conjunction with habitat loss, and climate change, has put at least 6,300 species—40% of all amphibians—at risk of extinction.
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Frogs thrived for over 200 million years, through two great extinctions before we decimated them within a few decades. In addition to signifying the violence of the Anthropocene Extinction, the story of chytrid contains valuable insights into the mechanisms and effects of the Anthropocene. Scientists have measured the economic, social, and environmental impacts of chytrid. They have investigated the features that make chytrid so lethal. They have tallied the losses and calculated extinction rates. These efforts have helped us better understand the Anthropocene and the world around us.
However, the economic and environmental impacts of extinction are only one facet of this extraordinarily complex issue. Numbers and statistics don’t tell the whole story. They alienate the countless nonhuman lives lost and the countless human lives changed as we drive our fellow species extinct. Tallying the losses of species and resources is important, but it is also important to tell the intensely personal, tragic reality of each extinction. Grief for the ebbing of the natural world is growing in diverse cultures around the globe. More and more people are beginning to feel the pain of extinction, of standing witness to the death of species they love. Perhaps no one is better situated to testify to the impacts and insights of witnessing extinction than the scientists who dedicated their lives to studying the fall of the frogs.
What is it like to see a species die in front of your eyes? What is it like to see 200 million years of evolution destroyed? What is it like to know that it’s humanity’s fault? Chytrid gives us a unique opportunity to examine the emotional impacts of extinction. For this essay, I contacted scientists who have worked on the front lines of the chytrid panzootic and asked them, What is it like?
Gaudiest of Anurans
Male Golden Toads cluster around a pool in Monteverde.
Photo by Michael and Patricia Fogden/Minden Pictures
“Those who have viewed at first hand the steep, dark-green, forest-covered slopes,” herpetologist Dr. Jay Savage has written, “with their ever changing aspect of sun and cloud, moon and mist, bright blue sky and bright green mantle, driving rain and boiling fog, come away with a feeling of overpowering awe and mystery.”
He was referring to Central America’s cloud forests where in 1964 he described Incilius periglenes, the Golden Toad. The male was a stunning golden color, which gave the species its common name. The equally marvelous female was speckled black, green, yellow, and red. In its formal description to science, Savage proclaimed the species to be “assuredly the most spectacularly colored [toad] known and […] among the gaudiest of anurans.”
The sole home of the Golden Toad was Monteverde Cloud Forest Biological Reserve in Costa Rica. It was here that in the spring of 1987, Dr. Martha L. Crump trudged through the damp, misty elfin forest to find what she described to me as the most incredible sight of her life: thousands of golden-orange toads gathered around pools on the moist forest floor. “It was a spectacle of amphibians!” There was something magical about the sight, she says, smiling. “It was a rainy day and the mud was brown and here were these brilliant orange toads just sitting on the ground. You got the impression that they were really something unique.”
Crump was so enamored with the toads that she got a grant from the National Geographic Society to return the next year. But things didn’t go as planned; Crump found only one toad. “I really wasn’t all that worried,” she recalls. “I was frustrated. I was disappointed that I hadn’t been able to do what I had wanted to do, but I wasn’t that worried.” It was a dry year, she notes. “Amphibians are unpredictable. I just assumed that it was too dry and they were still underground.”
The next year, Crump had her graduate student, Frank Hensley, complete her surveys. Hensley was delighted to have the opportunity to study the Golden Toads, but also found only one. He didn’t know that he was seeing the last of a species as he snapped a couple photos of the brilliant male, resting on a pad of moss by a pool of water. “I was thrilled!” says Hensley. “I assumed, he’s the first one up,” he notes. “We expected that as the rains picked up, the toads would come out and breed. I figured ‘here’s the first toad. I’ll come back tomorrow and there will be a dozen. I’ll come back the next day and there’ll be hundreds.’ I was so excited.”
All month, Hensley searched, but he never saw another Golden Toad. No one did. “They never came out,” he says. “They just never—that was it.” Though it would be many years before biologists came to terms with the loss, the toads were extinct.
The Silent Killer
“A sense of impending doom has enveloped the community of amphibian biologists.”
– David B. Wake, Facing Extinction in Real Time
Endangered Yellow-legged Frogs (Rana muscosa) lay dead of chytrid in one of their last mountain refuges.
Photo by Joel Sartore
In September of 1989, Crump attended the first World Congress of Herpetology in Canterbury, England. Several herpetologists inquired about how her studies of the Golden Toad were going. “Terrible,” she would reply. Many other members of the conference also reported the disappearance of their study populations, including Dr. David B. Wake, who would eventually go on to coin the term Sixth Extinction. “Over the course of the meeting,” Crump says. “So many people were saying the same thing. We all were realizing that something is going on.” The potential decline of the Golden Toad was not unique; amphibian populations were collapsing around the globe. Conservationist and herpetologist Dr. George Rabb was quietly listening to the reports and began launching an all-hands-on-deck emergency response by networking experts around the world.
Habitat destruction and over-collecting were known to be huge threats to amphibians, but instances like the Golden Toad seemed to rule them out as culprits of this mysterious spike in extinctions. “There were wild speculations,” Crump says. People suggested “everything from climate change to some kind of a pathogen.”
“We started realizing that something’s happening to the animals that we’ve been studying for, in many cases, decades.” Her tone softens as she recalls the confusion, the fear that she and her colleagues might be at fault. “People felt really bad. It was really this big black box.” The mystery was agonizing for the herpetologists studying amphibian declines, says Crump. What was happening? Were they causing this cataclysm?
The World Congress of Herpetology of 1989 sparked investigations into the enigmatic decline of the amphibians. As the extinctions mounted, scientists spent many frustrating years scrutinizing what they knew about the mystery. Ten years later, herpetologist Dr. Karen R. Lips collected evidence that helped scientists peg Batrachochytrium dendrobatidis as the cause of anuran declines. Had humans been innocent after all? If the fungus had only been present on one landmass, that would be a logical conclusion. But instead, chytrid had rapidly spread around the world. How did it spread? Most likely through the global amphibian trade and on international shipments of goods. The blame for chytrid doesn’t lie upon any individual, but upon humanity’s system of poorly regulated global trade. Nonetheless, the uncertainty, worry, and fear of this time still haunt Crump and others. “We just felt potentially very guilty,” she recalls. “We [humans] had been, if not the cause of amphibian declines, at least a great facilitator of spreading the pathogen.”
An Artificial World
“Noticing losses and mourning changes in our natural world is a sadness shared with all peoples; what is different for biologists is that we are distinctively positioned to catalogue the decline of species and to understand the true scope of it.”
– Karen R. Lips, Witnessing Extinction in Real Time
When I first spoke with herpetologist and forensic ecologist Dr. Joseph R. Mendelson III, I was taken by his cheerful personality and contagious enthusiasm for his work. They seemed at odds with the tragedies he’s witnessed over his decades as a herpetologist. He began his career in 1989, surveying amphibian communities in Mexico and Guatemala. He struggled to understand why his study sites were so barren of amphibians, chalking it up to his incomplete skills and eventually accepting the scarcity of amphibians as normal.
Years later, he was talking with his friend Karen Lips. “She was describing her field sites in Costa Rica and Panama,” recalls Mendelson, who was astonished when she told him she often found more than thirty frogs per night. He’d never seen such abundance in Mexico or Guatemala. “We looked at each other,” says Mendelson, “and it just hit us like a brick.” The chytrid had already wiped out Mexico’s frogs and no one had noticed. “I had arrived on the scene of a massacre.”
“I was having this completely artificial experience,” he reflects. “What I thought was natural probably was not.” Many scientists have increasingly tried to spread awareness of this fact: the Anthropocene Extinction is not a future event; we are in its throes right now.
In 2000, Mendelson and Lips began a new survey of Mexican ecosystems. This time, they visited sites for which historical amphibian population data were available. In some areas, less than 20% of species remained. “This place got annihilated when no one was looking,” Mendelson says. “Mexico is no longer normal.”
The last vestiges of the anuran fauna were being lost right as Mendelson and Lips were executing their study. One day, Mendelson stood with Lips by a rushing stream on a steep mountainside in southern Mexico. A frog twirled through the flow of the water, belly up. He scooped it from the cool, frothing stream and instantly knew what species it was: Quilticohyla erythromma. Something, he could tell, was terribly wrong with the frog. It lay stiff in his hands, its moist green skin cool against his palm, its bright red eyes gleaming. Then it died. No one ever saw Quilticohyla erythromma again. The species was extinct. Mendelson kept the frog’s body and it later tested positive for chytrid. I can see the pain on Mendelson’s face as he tells me this. “It died in my hand,” he says, his horror still evident.
As terrible as this experience was, Mendelson would soon have an even more intimate run-in with extinction. So I ask my next question: “What was it like caring for the second to last Rabbs’ Fringe-limbed Treefrog?” Mendelson shakes his head. “Man, that was heartbreaking,” he says, looking away. “That was really tough.”
Ghosts In Glass Boxes
“Frogs in glass boxes are ecological ghosts.”
– Joseph R. Mendelson III, Frogs in Glass Boxes: Responses of Zoos to Global Amphibian Extinctions
Illustration by Saiman Chow
Mendelson and Lips knew they only had one shot at saving Panama’s remaining frogs and they knew there was only one way to do it: the frogs had to be taken from the wild. It would be a gamble, but after a decade of research, they had found no other option. It was their “moral and ethical responsibility,” says Mendelson.
In the Spring of 2005, Mendelson, Lips, and Ron Gagliardo helped lead a group of dedicated conservation biologists to a nature reserve near El Valle de Anton in Panama to execute their plan. At El Valle, they found a brilliant forest filled with beautiful, healthy frogs. Knowing time was of the essence, the herpetologists worked at a mad pace to evacuate frogs from the preserve. They would slip into the forest at night and grab as many frogs as possible. To feed the frogs, they kept them in rented rooms filled with rotting fruit to attract flies. Some of the captured frogs stayed in this “frog hotel” with local herpetologists Edgardo Griffith and Heidi Ross; this was the basis for the now-formalized El Valle Amphibian Conservation Center. They stuffed hundreds of other frogs into their carry-on baggage and “air-lifted” them to Atlanta. After months of this insanity, the chytrid arrived, the corpses piled up, and El Valle became as desolate as Mexico.
The rescue mission garnered captive populations of 18 species. The one that most enamored Mendelson was a large, undescribed treefrog, with the spectacular ability to glide through the canopy with its webbed toes. Mendelson and his colleagues formally described it as the Rabbs' Fringe-limbed Treefrog (Ecnomiohyla rabborum) in 2008, by which time it was likely already extinct in the wild. The frog was named in honor of George and Mary Rabb in recognition of their tireless efforts to conserve biodiversity and especially amphibians.
The scientists worked quickly to breed the frogs in captivity, and though they had success with many species, the Rabbs’ Treefrog wasn’t among them. As the years wore on, the frogs began to die of old age, and teams at Zoo Atlanta, El Valle Amphibian Conservation Center, and Atlanta Botanical Garden tried frantically to breed them before it was too late. As the clock wound down for Mendelson, time had run out for Lips. The chytrid wave had crashed, washing the frogs away. Many of the frogs from El Valle were “safe” in cubes of glass, living out their days in zoos. Yet back in Central America, the streams burbled quietly, a sorrowful silence replacing the croaks, chirps, and kerplunks of frolicking frogs. Lips’s words convey a strange emptiness as she realized what had happened. “I look at the folders of data in my office and think about the descriptions and field guides we started that don’t seem very useful anymore,” she writes. “It’s hard to believe that in just 15 years, I’ve watched dozens of species go extinct. It’s harder still to accept that [...] we haven’t been able to save a single species. Not one.” Yes, some species live on in zoos, but does that count?
Dead On Arrival
“I have seen my career vacillate between the thrill of discovering new species and the chill of tracking extinction events—including species that I described. Taxonomists are not the warmest lot of people, but I will opine that one feels a personal connection with a species that you yourself have named.”
– Dr. Joseph R. Mendelson III, Shifted Baselines, Forensic Taxonomy, and Rabbs’ Fringe-limbed
Treefrog
One of the last Rabbs' Fringe-limbed Treefrogs.
Photo by Brad Wilson
Eventually, most of the Rabbs’ Treefrogs died of old age, leaving only two males and one female. Mendelson and others worked hard to breed them, but in 2009, tragedy struck. “I remember when I got the phone call one day that the female died,” says Mendelson. He sat, stunned, at his desk. “I thought, ‘Wow, this is what it feels like. That species just went extinct.’ But nobody bothered to tell the last two males. I thought, what a gut-wrenching and odd experience to look at something that you know is extinct. It was a heart wrenchingly slow process to watch that species go extinct right in front of me.”
Eventually, the frog Mendelson cared for at Zoo Atlanta began to grow old. The frog was “still happy” but Mendelson could tell by his slower, stiffer gait that he was reaching the end of his life. The frog soon began to suffer from his condition and was euthanized on February 17, 2012. To my knowledge, exactly two articles were published on the tragedy: one by Mendelson and one short piece in Scientific American. Four years later, in September 2016, the last Rabbs’ Treefrog died at the Atlanta Botanical Garden and the species went extinct.
Mendelson’s experiences with the death of species are far more intimate than most of ours, but his story warns of the dark territory we are entering. Herpetologists are not documenting a rare event, but the beginning of the disaster that will define this century. They were imparted painful wisdom by the amphibian canaries in Earth’s coal mine and we must listen to them before it is too late.
Reflections
“Amphibians are all but gone, bequeathing us lessons that must not be squandered.”
– Joseph R. Mendelson III, Lessons of the Lost
Writing this essay has been a journey for me, a far more emotional and insightful one than I could have ever imagined. At times, I laughed as I wrote, at others I was close to tears. I am deeply grateful to Martha Crump, Frank Hensley, and Joseph Mendelson for sharing their experiences. My last question to them was, What are your main takeaways from what you’ve witnessed and what do you want others to know?
Hensley responds that he is considering taking a trip back to Costa Rica with his son, but that they don’t plan on visiting Monteverde. “I can take him back to Monteverde,” Hensley says. “But I can’t show him a Golden Toad. I can hike the trail that I hiked every day, but there won’t be any Golden Toads.” He says he feels privileged to have seen the toad and saddened that future generations will never have the same opportunity. “It’s a bittersweet kind of thing. I’m incredibly grateful. I kind of feel honored that I’m one of the few who ever got to see one. But of course, I’m also horribly disappointed that the Golden Toad is gone.”
Crump’s feelings are similar. “The loss of the Golden Toad made me so much more aware of how we humans are affecting our surroundings because it affected me directly,” says Crump. “If we don’t wake up to what we are doing,” she observes, “Our planet will be a totally different world for future generations.” Expanding on that idea, Hensley notes that the Anthropocene extinction is fueled by “greed and a lack of love for our fellow humans.” These root causes, he says, “must be addressed by being better stewards not only of the Earth, but of our own species in particular.”
Mendelson highlights the urgency of this issue and the dark consequences of inaction. “There is a parallel between what amphibian taxonomists do these days and what homicide detectives do,” he claims. “Both arrive at scenes of mayhem. Maybe they solve the crime, but they are powerless to undo it.” It’s “heart wrenching,” he says. “We really, really need to stop letting this happen. This has got to stop.”
Darkness and Light
“We transform the future’s unknowability into something certain, the fulfillment of all our dread, the place beyond which there is no way forward. But again and again, far stranger things happen than the end of the world.”
– Rebecca Solnit, Hope in the Dark: Untold Histories, Wild Possibilities
The emotional and psychological effects of extinction are not well studied. However, my interviews with three experts, complemented by extensive reviews of the literature reveal that the emotional realm of extinction is broad and complex. Countless interwoven and even contradictory emotions can arise from witnessing extinction. “Darkness and light exist at the same time,” Dr. Andrea Bonior, professor of psychology at Georgetown University, tells me. Even in the midst of mass extinction, she says, “there’s joy and gratitude and beauty, a sense of awe, while there is also sadness and grief. These herpetologists have experienced something beautiful at the same time as experiencing the tragedy of it,” says Bonior.
Through this complexity shines one important truth: extinction is death. Its toll is that of loss. From despair to gratitude, the psychological toll of extinction is the swirling fog of emotions that comprise grief. It manifests in the pain of herpetologists witnessing the extinction of Central America’s anurans and the despair I feel as I watch my beloved Monarch Butterflies race toward extinction in North America. Everyone on Earth has been touched by ecological loss. Yet society is failing to address the immensity of this loss. With almost no conversation around ecological grief, we become overwhelmed by extinction. This has long fueled inaction on confronting it.
We must accept our grief. Opening society to ecological grief will allow us to combat extinction more effectively. To grieve for the loss of our fellow species is to truly realize, even deepen, our love for them. Connection to the natural world is something we all have in common. Mourning extinction together helps us to recognize this shared value and unifies us in our effort to protect Earth. If we grieve and care together, then we can nurture a love for our planet, its nonhuman inhabitants, and each other.
How can we both acknowledge the tragedy of the Anthropocene, while remaining hopeful and empowered to keep fighting? The answer lies in a concept which activist Rebecca Solnit has coined Hope in the Dark. Solnit appreciates that the world looks increasingly dark, and to remain optimistic is to deny the tragic reality of our time. One of the core ideas of this concept is that authentic hope doesn’t arise from optimism, but from remembering that the future is not monochrome and not certain.
We can welcome this complexity and uncertainty or we can despair, viewing the future as “the fulfillment of all our dread.” Despair prohibits us from making a difference, while accepting that the future is unwritten allows us to become its authors. “Wars will break out,” notes Solnit, “The planet will heat up, species will die out, but how many, how hot, and what survives depends on whether we act. The future is dark, with a darkness as much of the womb as the grave.”
These scientists’ stories have helped me to comprehend what it means for a species to be lost forever, while inspiring me with their passion and determination. I hope they do the same for you. If everyone understands and feels the tragedy of all that we’re losing, I believe we can come together with care and unity to preserve the natural world. We can create a future where all species can thrive, where streams and pools again come alive with amphibians, and where the frogs’ choruses will once again ring out through the night, filling our world with beauty and wonder.
Two of the last Rabbs’ Treefrogs huddle together during their rescue in El Valle de Anton.
Photo by Ramon da Pena