Some people spend a long time deciding what they want to do in life. Hazel McBride feels lucky that she’s always known. As a child in Scotland, she watched a VHS tape of Free Willy on repeat. That was the first time she felt a connection with killer whales. The second time was at age eight, on a trip to SeaWorld Orlando in 2000. Shamu was the animal world’s greatest celebrity, and in the US, SeaWorld ads were ubiquitous. Kids wanted to see the killer whales, and after they saw them, they told their parents they wanted to become killer whale trainers. McBride actually did it.

It wasn’t easy. Scotland didn’t have a SeaWorld, or warm water, or anywhere, really, where McBride could get experience with marine mammals. She had horses she cared for, and she was on the national swim team – a modest start. She sent out volunteer applications to local zoos and worked with California sea lions at a safari park. She reached out to trainers online and one told her a psychology degree would help, so she got one.

When it was time for her to get “dolphin experience” – a rung up the career ladder (and food chain) toward orcas – she interned abroad in the Bahamas and Florida, prepping buckets of dolphin food and giving educational briefings. She graduated from the University of Glasgow and started applying for jobs.

But killer whale gigs are competitive; McBride’s first full-time gig was still with dolphins, in the Dominican Republic. Then, in 2015, a space opened up on the orca team at Loro Parque in Spain. After a lifetime preparing, she had the career she’d always dreamed of. She was, finally, in charge of a killer whale.

There was only one problem: Blackfish had premiered.

Blackfish, a 2013 documentary, argues that beneath the feel-good facade of orca shows are sick and miserable whales, and trainers in lethal danger. The film centers the 2010 death of the SeaWorld trainer Dawn Brancheau to make a powerful case against orca captivity.

Orca researchers interviewed in the film say that orcas captured in the wild at a young age become violent, particularly when forced to perform and breed by their captors. Blackfish argues that Brancheau’s killing by Tilikum, a particularly aggressive orca, is a result of SeaWorld’s cruelty toward the social, hyper-intelligent species. Blackfish then links her death to other fatal orca incidents, including the 2009 death of the trainer Alexis Martínez at Loro Parque, McBride’s employer.

The film – a masterclass in emotional exposé that reoriented the consciences of marine park goers in favor of the animals’ rights – was wildly popular. It had 21 million viewers the month it premiered on CNN, after its theatrical run. SeaWorld stock plummeted, and the park began offering tickets at as deep a discount as 46%. Proposed bans on whale captivity and the use of orcas for entertainment rippled through state legislatures.

Online, the hashtag #EmptytheTanks proliferated, with fans of the film staging campaigns to pressure corporate sponsors into dropping their SeaWorld partnerships, or singers to cancel their shows at the parks. By 2015, SeaWorld had reported an 84% drop in profit compared with 2014 as attendance shrank.

The impact on the industry went far beyond its best-known park brand. McBride woke up one morning in Spain and found out that orca breeding, one of the most controversial aspects of orca captivity, was subject to a ban at her own place of work. She was furious. The International Marine Animal Trainers’ Association (Imata), the organization that develops criteria for marine animal training, was publicly silent but privately furious, too.

In a recording of an Imata panel posted to YouTube in 2014, an attendee asked the then chair of the public relations and promotion committee, Michael Hunt, what he thought of the movie. He, and everyone else who spoke on the panel, seemed disgusted by it.

“What movie did we pay for … Man of Steel?” Hunt said, describing his own filmgoing experience. “And we snuck into Blackfish so that way they didn’t get our money.”

The crowd, including trainers who had dedicated their lives to working with captive marine mammals, erupted into applause and laughter. And again and again as the panel’s plan emerged: “This is not about the United States, this is about the whole world. We need some material … to show in other countries in other languages so everybody can see the other side, the real and the true side of this story.” Applause. “Be truthful when you’re on TV… Don’t get caught in a lie. And tell them you want to do live interviews. Live interviews they can’t edit, and they can’t make you look stupid.” More applause.

They’d found their saving grace: though the trainers played a major role in killer whales’ captivity, Blackfish did not paint them as the bad guys. “That gives us a little bit of an advantage as we craft our message,” Hunt could be heard saying. “As we move forward, we need to be out there proactively telling our story.”

The marine mammal training industry has been in the midst of an identity crisis ever since.

I never sought McBride out. She appeared organically, on my Instagram feed, years later, doing just what Hunt had urged. It was 2021, and I saw a photo of her pressing her cheek to a killer whale’s mouth. She had also self-published a memoir and defense of killer whale training, I Still Believe, and soon started hosting a podcast, on which she interviewed former killer whale trainers, while keeping up a YouTube channel, Tiktok account, and blog.

“The hardest thing about speaking openly and publically [sic] about killer whales? The constant repetition and nitpicking. My words are my own. If they don’t serve you? Leave. It’s that simple,” she’d written in the post that crossed my feed. “My first priority has always been standing up for trainers and giving us a voice.”

After two years at Loro Parque, McBride had moved on to a senior killer whale training role at Marineland in southern France, a seemingly blissful time. In a recording of her Marineland show, she beams as two orcas cry out their songs for her, on cue. Later in the show, she blows an orca a kiss, and it responds with a little opening of its mouth back. She described Wikie, an orca there, as her “soul animal”.

“She’s the most interesting being I’ve ever met in my entire life,” she later told me.

But things have changed in the decade since Blackfish. Many trainers feel the added public attention around the killer whale captivity debate has not only destroyed any chances of holding on to their dream jobs, but also made them pariahs. McBride told me that an older trainer she knew had said his job used to function as a pickup line at bars. After Blackfish, it was more likely to get a drink thrown in his face than get him laid. Another former trainer told me she struggled with burnout amid all the public scrutiny; she now works as a deckhand on a boat.

As groups like Imata walk the line between angry trainers and a marine park-going public that is now aware of the captive orca’s plight, some American and European trainers are traveling further afield for work – often to Asia. Meanwhile, captive orcas remain, well, captive – and in some countries, their numbers might be increasing.

“I feel fortunate to be one of the endangered species myself,” Grey Stafford told me. “A killer whale trainer.”

Stafford, Imata’s president and board director for several years in the 2010s, was also a trainer in the 90s. He decided to become one in 1989, when he and his fiancée went to SeaWorld Ohio and witnessed three apex predators – a human, a bottlenose dolphin and a killer whale – swim alongside each other. That’s when he knew.

The 90s were “the glory days” for trainers, Stafford says. Sure, there were anti-captivity folks back then, but “you could literally just have one spokesperson comment, respond to questions or criticism by detractors, and then it would go away,” he said. “Those days are long gone.”

By 2024, Stafford was still speaking out on behalf of animal trainers as a podcaster. He recently wrapped an episode about SeaWorld Ohio and “what we lost when she closed her doors”. I asked him what we had lost.

“We have a generation or two now that, unlike you, have not seen human beings in the water with killer whales,” he said. “And that is something precious that has been lost.”

For perspective, Deborah Giles, a killer whale researcher at the University of Washington, says that orca captivity “would be like putting us [humans] in a bathroom, or something that small”.

“These are not well adapted animals for the environment that we’re forcing them into,” she said.

Though marine scientists – including Giles – stand by the facts in Blackfish, certain discrepancies on the production’s part laid the groundwork for SeaWorld’s rebuttal. SeaWorld noted that video clips occasionally showed a different orca than the one being discussed in the narration, and that Blackfish relied on sources who’d formerly, not concurrently, worked at the park. It said that Blackfish didn’t mention how SeaWorld “rescues, rehabilitates and returns to the wild hundreds of wild animals every year” and “commits millions of dollars annually to conservation and scientific research”. Blackfish was “inaccurate and misleading”, the park claimed.

None of this denies that Tilikum killed three people, or that killer whales are better suited to life in the wild. “Their social bonds, which are broken when they’re taken from their family and put into captivity, is part of the very essence of the species, and yet we break that when we take them away,” Giles said.

Nevertheless, McBride and many of her fans want to return to marine parks’ pre-Blackfish heyday. Parades of heart emojis cascade through the comments below each orca pic McBride posts, and fans write in to share their happy memories of killer whale shows. McBride believes Blackfish was overly sensational, and that the people who care for orcas daily are the ones most equipped to determine what’s best for them. Likewise, many of her followers disparage the claims made in Blackfish. “Blackfish 👏 is 👏 NOT 👏 a 👏 resource 👏,” said one commenter.

McBride is far from the only trainer advocating for a return to the pre-Blackfish status quo on social media. Another trainer-run account, @Truth4Toki, lobbied against Tokitae’s planned release from the Miami Seaquarium to her native waters in the Salish Sea. Like McBride’s page, Truth4Toki argued that trainers knew better than anti-captivity activists what was best for the animal. Its bio boasts that the group has over 300 collective years of experience working with Tokitae. (Tokitae died in a Miami Seaquarium tank in August after more than 50 years in captivity.)

Part of Stafford’s argument for killer whale captivity is that we wouldn’t know as much about the species if we’d never captured them.

“In terms of the specific skills of working with a killer whale, those skills are going away,” he said. “What happens when we lose that human capital, the people who know how to disentangle whales off the coast of California? The people who understand maternal behavior? That is going to die out.”

I asked Giles what she thought about that. She offered that when captive facilities started, “We didn’t know better. We just frankly didn’t know how intelligent these whales were.” Now we do.

Reflecting on her first trip to SeaWorld, McBride wrote in her memoir: “Looking back it almost seems as if I started out in my career at exactly the wrong time.”

Stafford, however, doesn’t believe the dream of training in a pre-Blackfish world is dead. “Here’s the truly ironic thing,” he said. “The best killer whale training that’s happening right now is in east Asia.”

Moving to China was never Steve Hearn’s plan. But when a Chinese property developer approached the marine mammal trainer in 2018 about a job opportunity on the island province of Hainan, he was open minded. Hearn, a 30-year industry veteran, was working at a dolphinarium in the Netherlands, where he had “always worked under a certain amount of activist pressure”. But, he said, “the last 10, 15 years has been a lot worse.”

R&F Properties’ vision for Hainan Ocean Paradise impressed Hearn; he visited the site as it was under construction and marveled at the size of the holes in the ground. He was offered a position overseeing more than 100 mostly Chinese trainers and began teaching them how to work with marine animals according to Imata standards. The park was also the mainland’s first to publicly eschew the controversial practice of wild capture, displaying only animals that had been rescued, says Hearn (though animals that had been previously wild-captured by other parties could still count as rescues). It did not house orcas.

That level of regard for the animals’ provenance and care is rare among the Chinese facilities that do house the animals, according to Taison Chang, chairman of the Hong Kong Dolphin Conservation Society.

Pre-Covid, Chang made a trip to visit some facilities on the mainland, including Chimelong, the self-proclaimed “Orlando of China”. The $2bn Chimelong Ocean Kingdom, which opened the year after Blackfish premiered, housed nine wild-caught orcas, and in 2017, it celebrated becoming China’s first orca breeding facility. The China Cetacean Alliance (CCA) estimated that, as of 2019, there were 80 ocean parks in China, the majority of which held whales or dolphins in captivity, and another 27 were under construction.

“I was very convinced that the condition of the facilities was poor,” Chang said of the parks he visited. Tanks were sometimes small and poorly maintained, the animals living too densely together. In some instances, species from wildly different habitats shared the same tank.

Chang said the number of marine animal facilities in China would hit 100 soon. China, however, is new to marine park development. And none of this development would have been possible without the help of trainers and marine park experts from the west.

“There has been a trend that facilities, especially the big ones like Chimelong and Haichang [Ocean Park, in Shanghai], are hiring trainers from the west. They are often portrayed as the ‘star’ trainers,” Chang said. This echoed Hearn’s experience at events for Hainan Ocean Paradise: “I had to be there because it was a foreign face showing that we’re investing correctly in all of our aspects of our park.”

That might be due to China’s poor reputation for marine animal welfare. As of 2019, CCA was aware of at least 15 orcas held in captivity in China (the US has 18, all of them at SeaWorld parks), and 14 Chinese parks claimed to have bred marine mammals in captivity. Of the 37 whale or dolphin births CCA was aware of, at least seven of the calves died. The last calf to be born under SeaWorld’s breeding program died in 2017, a year after SeaWorld announced plans to end captive orca breeding.

As SeaWorld struggled to rebrand itself post-Blackfish, China’s Zhonghong Group acquired a 21% stake in SeaWorld Entertainment Inc, making it the largest shareholder, with SeaWorld agreeing to advise the group on future parks abroad. (It terminated the agreement two years later when Zhonghong defaulted on a loan.)

Hearn, though not affiliated with SeaWorld, confirmed the demand in China for western marine park expertise: When I spoke to him in February, he was planning on traveling to Shanghai to consult on three additional marine parks.

When I asked Chang if he saw killer whale captivity continuing to grow in China, he said: “Definitely.”

Killer whales have not always been an entertainment commodity. A hundred years ago, they were more likely to be cast as monsters than have their likenesses made into stuffed animals.

The change, the historian Jason Colby argues in his book Orca, came mid-century, when industry in the Pacific north-west shifted from reliance on extractive, labor-intensive jobs to a middle-class leisure economy. Orcas were no longer seen as a daily threat to fishermen. Instead, they were marvels – to the white majority of the region, anyway; members of the Lummi Nation say they have always seen orcas as their relatives. The first wild captures for captivity occurred in this region. Like elephants before them, orcas soon became a “marquee” animal, solidifying a certain park’s status and drawing more spectators.

Paradoxically, Americans’ heightened awareness of killer whales led to greater conservation efforts, which in turn paved the way for today’s anti-captivity movement. (One subspecies of orca, the Southern Resident orca, remains endangered today.)

Colby tells me he’s fascinated by the number of people he’s met whose transformative encounters with orcas in captivity as children, despite being positive, were the launching pad for anti-captivity activism. I tell him about a reverse scenario: that I’d spoken to a killer whale trainer who was first inspired by Free Willy, a movie about releasing a whale into the wild. “That movie doesn’t even work if you don’t have captive orcas,” he pointed out.

I asked everyone I spoke to what drew them to the ocean’s fiercest predator. Stafford called swimming with orcas “a thrill that I will never enjoy again in my life”. Several people pointed out that orcas are black and white, which, if you think about it, is pretty cool. Others talked about having early visions of orcas as if they’d been Inception-ed into their brains.

Giles recalled a vivid dream she’d had as a child, in which she changed places with an orca stuck in a pool. There was no reason for orcas to feature so prevalently in her psyche; she grew up on a worm farm.

A former SeaWorld trainer, Kyle Kittleson, told me: “I was born this way.

“I was born a man. I was born gay. And I was born with a love of marine mammals.”

Like McBride, Kittleson spent years in his landlocked hometown scheming ways to get marine animal experience. When he finally landed the interview at SeaWorld Orlando and traveled to Florida, it had to be rescheduled; it was the day Tilikum killed Dawn Brancheau.

Maybe it’s just that lifelong dreams are hard to shake, but even Brancheau’s death didn’t phase Kittleson. He eventually worked in the same stadium she had, loving the crazy-intense swim test he had to pass to even be considered, the parrots he fed and bonded with, the jacket that said “SeaWorld” on it.

But things were different after Brancheau died. More government regulation creeped into Kittleson’s work, and he disagreed with the new rules. And then came Blackfish – “a piece of propaganda that was meant to evoke feelings rather than logic from the viewer”, he claimed – and public opinion shifted underneath him.

Kittleson eventually quit the profession but continued to defend killer whale training online and self-published a guidebook for aspiring trainers, Wear a Wetsuit at Work. Today, though, he’s one of several trainers I spoke to who has pivoted almost entirely away from the field. Kittleson currently runs the educational YouTube page Baba Blast! for kids. He likes his work, even if it’s not what he spent his childhood dreaming about.

Imata, meanwhile, continues to quietly defend its own existence. Throughout the 2010s, its annual conference featured pro-captivity speakers like the former trainer Mark Simmons, the pro-SeaWorld voice in Blackfish. More recently, Imata leader Hunt joined Stafford on his podcast in honor of the organization’s 50th anniversary, in 2022. (Hunt could not be reached for comment.) This month, Imata’s annual conference featured a behind-the-scenes tour of SeaWorld San Antonio, home to five killer whales.

McBride, too, made a career pivot. In September 2020, she released a YouTube video announcing plans to leave her job at Marineland to be closer to her boyfriend during the pandemic. It was titled The Hardest Decision of My Life.

“If you are an aspiring trainer out there, I want to let you know that your identity outside of the job is also very important,” McBride said, tearfully, into the camera. “At the end of the day, sometimes it is just a job.”

These days, she’s still posting in support of orca captivity. But her new job, social media manager for a non-profit in the Netherlands, really is just a job.

Sounds of the natural world are rapidly falling silent and will become “acoustic fossils” without urgent action to halt environmental destruction, international experts have warned.

As technology develops, sound has become an increasingly important way of measuring the health and biodiversity of ecosystems: our forests, soils and oceans all produce their own acoustic signatures. Scientists who use ecoacoustics to measure habitats and species say that quiet is falling across thousands of habitats, as the planet witnesses extraordinary losses in the density and variety of species. Disappearing or losing volume along with them are many familiar sounds: the morning calls of birds, rustle of mammals through undergrowth and summer hum of insects.

Today, tuning into some ecosystems reveals a “deathly silence”, said Prof Steve Simpson from the University of Bristol. “It is that race against time – we’ve only just discovered that they make such sounds, and yet we hear the sound disappearing.”

“The changes are profound. And they are happening everywhere,” said US soundscape recordist Bernie Krause, who has taken more than 5,000 hours of recordings from seven continents over the past 55 years. He estimates that 70% of his archive is from habitats that no longer exist.

Prof Bryan Pijanowski from Purdue University in the US has been listening to natural sounds for 40 years and taken recordings from virtually all of the world’s main types of ecosystems.

He said: “The sounds of the past that have been recorded and saved represent the sounds of species that might no longer be here – so that’s all we’ve got. The recordings that many of us have [are] of places that no longer exist, and we don’t even know what those species are. In that sense they are already acoustic fossils.”

Numerous studies are now documenting how natural soundscapes are changing, being disrupted and falling silent. A 2021 study in the journal Nature of 200,000 sites across North America and Europe found “pervasive loss of acoustic diversity and intensity of soundscapes across both continents over the past 25 years, driven by changes in species richness and abundance”. The authors added: “One of the fundamental pathways through which humans engage with nature is in chronic decline with potentially widespread implications for human health and wellbeing.”

The shift in ecosystem sound is happening in the air, the forests, the soil, and even under the water. During the cold war, the US navy used underwater surveillance systems to track Soviet submarines – and found they struggled to do so near coral reefs due to all the sounds reefs produced. It wasn’t until 1990 that civilian scientists could listen to this classified data.

“Whenever we went to a healthy reef it blew our minds – the cacophony of sounds we heard,” said Simpson, who has been monitoring coral reefs using hydrophones for more than 20 years. “A healthy reef was a carnival of sound.”

At the outset of his research, noise pollution from motorboats was his main concern, but 2015 and 2016 brought significant bleaching events, which resulted in 80% mortality of corals. “They cooked the reef,” he said. More than half of the world’s coral reef cover has now been lost since 1950. If global heating reaches 2C, more than 99% of coral reefs are expected to start dying.

The result of these bleaching events is a “deathly silence”, said Simpson. “We swam around those reefs crying into our masks.”

“These sounds and silences speak back to us like in a mirror,” said Hildegard Westerkamp, a Canadian sound ecologist who has been recording soundscapes for half a century, during which time wildlife populations have experienced average declines of almost 70%.

She started working on the World Soundscape Project in 1973 with the intention of documenting disappearing ecosystems. “We proposed to start to listen to the soundscape, to everything, no matter how uncomfortable it may be – how uncomfortable the message.”

She said: “The act of listening itself can be both comforting and highly unsettling. But most importantly it tends to connect us to the reality of what we are facing.”

Sound data is now being used alongside visual data as a way to monitor conservation efforts and ecosystem health. More sophisticated and cheaper recording equipment – as well as increasing concerns about environmental destruction – are driving the boom in ecoacoustic monitoring.

As the sophistication of microphones has increased, scientists are using them to monitor life that would not usually be audible to human ears. Marcus Maeder, an acoustic ecologist and sound artist from Switzerland, has been investigating the noises trees make under stress, pushing a microphone into the bark of a tree to listen to the living tissue. Stress sounds like pulses come from within the cavity, he said.

When he first pushed a microphone into the soil of a mountain meadow he discovered it was also alive with noise, “a completely new kingdom of sounds”.

Intensively managed agricultural land, often doused with pesticides, sounds very different, Maeder said: “The soil becomes quiet.”

For many researchers, disappearing soundscapes are a source of grief as well as of scientific interest. “It’s a sad thing to be doing, but it’s also helping me tell a story about the beauty of nature,” said Pijanowski. “As a scientist I have trouble explaining what biodiversity is, but if I play a recording and say what I’m talking about – these are the voices of this place. We can either work to preserve it or not.

“Sound is the most powerful trigger of emotions for humans. Acoustic memories are very strong too. I’m thinking about it as a scientist, but it’s hard not to be emotional.”

Find more age of extinction coverage here, and follow biodiversity reporters Phoebe Weston and Patrick Greenfield on X for all the latest news and features

The tale starts 30 years ago, when Bernie Krause made his first audio clip in Sugarloaf Ridge state park, 20 minutes’ drive from his house near San Francisco. He chose a spot near an old bigleaf maple. Many people loved this place: there was a creek and a scattering of picnic benches nearby.

As a soundscape recordist, Krause had travelled around the world listening to the planet. But in 1993 he turned his attention to what was happening on his doorstep. In his first recording, a stream of chortles, peeps and squeaks erupt from the animals that lived in the rich, scrubby habitat. His sensitive microphones captured the sounds of the creek, creatures rustling through undergrowth, and the songs of the spotted towhee, orange-crowned warbler, house wren and mourning dove.

Back then, Krause never thought of this as a form of data-gathering. He began recording ecosystem sounds simply because he found them beautiful and relaxing. Krause has ADHD and found no medication would work: “The only thing that relieved the anxiety was being out there and just listening to the soundscapes,” he says.

Inadvertently, he had begun to gather a rich trove of data. Over the next three decades he would return each April to the spot at the bigleaf maple, set his recorder down and wait to hear what it would reveal.

But in April last year, Krause played back his recording and was greeted with something he had not heard before: total silence. The recorder had run for its usual hour, but picked up no birdsong, no rush of water over stones, no beating wings. “I’ve got an hour of material with nothing, at the high point of spring,” says Krause. “What’s happening here is just a small indication of what’s happening almost everywhere on an even larger scale.”

A rich weave of sound fades

Animals produce a vast array of sounds: to find mates, protect territories, identify offspring or simply by moving about. But traditionally, ecologists have measured environmental health by looking at habitats rather than listening to them. Krause developed the idea that the sound of healthy ecosystems contained not only the calls of individual animals, but a dense, structured weave of sounds that he called the “biophony”.

In 2009, when Krause listened through his archive, he realised a story was emerging: a subtle but noticeable loss in the density and variety of natural sounds.

At the same time, he began observing odd things happening in Sugarloaf Ridge park. Leaves on some tree species were unfurling two weeks earlier than documented in historical records. The change in bloom meant migrating birds following the Pacific Flyway were out of sync with sources of food along their route. Winter rain patterns had changed. Then in 2012, exceptional drought conditions started. California had been getting little rain and record hot temperatures, which pushed the parched land into unprecedented territory.

By 2014, northern California was experiencing its most serious drought in 1,200 years, and the bird song in Krause’s recording becomes muted.

In 2015, the quiet sets in. There is no stream flow or wind in the audio. In 2016, the hush is broken only by the call of a purple finch.

“A great silence is spreading over the natural world even as the sound of man is becoming deafening,” Krause wrote in 2012, in his book The Great Animal Orchestra. “The sense of desolation extends beyond mere silence.”

Life swept away by fire

Then, in 2017, the Tubbs fire struck, the most destructive wildfire in northern California’s modern history.

Krause happened to be awake at 2.30am on the October morning when the flames reached his home. He and his wife had to run through a wall of fire surrounding the house. “Except for us, not one single item that we had amassed over the arc of our lives survived,” he says. “As we raced toward the car, a fire tornado seethed with a voice of rage.

“That sound haunts us to this day,” he says. “I rarely make it through a night without awakening to frightful sonic nightmares.”

Propelled by gusts of 78mph, the fire incinerated entire neighbourhoods. Krause’s cats, Seaweed and Barnacle, died. He lost 70 years of letters, photographs and field journals, in flames so intense they left the refrigerator an unrecognisable puddle of aluminium and steel. His precious recording archive survived, in copies stored elsewhere.

The Tubbs fire burned 80% of Sugarloaf Ridge park. John Roney, the park manager, managed to evacuate 50-60 campers as the fire roared towards them.

The bigleaf maple survived. It stood up to the fire,” says Breck Parkman, a retired state parks archaeologist. “It lost branches and got partially stunted, but it survived.” But in September 2020, the Glass fire hit: one of nearly 30 wildfires across California that month.

“That pretty much finished off what was left of that tree,” says Parkman. He remembers once taking Clint Eastwood to look at it, as well as some botanists trying to establish if it was the biggest maple in the American west – they never confirmed its status. “It didn’t really matter, though. The birds knew the tree was grand. For them, this was the tree of life,” he says.

He believes the tree should have lived for a few hundred more years and likens it to an elder at family gatherings who brings wonderful food. One day that person disappears. “It’s a type of sadness – it’s hard to describe,” he says.

“It’s a loss, and there’s a longing. I would suspect the birds still miss that tree. I do.”

Many forest ecosystems are reliant on fire to decompose dead wood and old leaves but historically these tended to be smaller fires. They did not typically burn the tree canopy, so insects and other animals could take refuge without getting scorched. The larger fires in recent years are much hotter and threaten endangered species that have restricted ranges.

Desirae Harp, an educator at the state park and member of the local Mishewal Wappo tribe, says the silence that fell after the fires broke her heart.

“Hearing that silence, of all those native plants and animals, is heartbreaking because those are our relatives. I feel like when human beings die we call it genocide. But when we destroy whole ecosystems, we don’t always understand the weight of that.”

A silent message to the world

One of the most significant environmental books of the 20th century is Silent Spring by Rachel Carson. Published in 1962, it warned that if people did not stop their destruction of nature, especially through the use of pesticides such as DDT, the number of birds and other wild creatures would continue to decline and silence would begin to fall over the natural world.

In Krause’s recording from April 2023, not only is the birdsong missing, but there is no water in the creek either. “We’re watching this in our own lifetime, which is startling,” he says.

Comparison of 2003 and 2023:

In 2019, Krause argued that the climate crisis could be “changing the Earth’s natural acoustic fabric”. He drew an analogy between the natural world and a concert hall: if the heat and moisture of the concert hall changed, so too would the players’ ability to perform.

“The same is happening for Earth’s orchestra. New atmospheric conditions are detuning natural sounds,” he wrote. “Only major mitigation actions will help preserve Earth’s beat.”

One of the reasons people were first drawn to Sonoma county, where most of the state park lies, was to go fishing, hunting and swim in the creeks. In the 1970s there were many places to swim, says Steven Lee, a research manager at Sonoma Ecology Center. “People don’t swim in the creeks here any more. Why not? Because there’s not enough water.”

The biodiversity associated with the streams has also been lost. Chinook salmon and steelhead trout are unable to reach their spawning grounds if there is no water. “It’s definitely drastic,” says Lee, about Krause’s latest recording. “The pessimist in me would say that we’re probably going to see a lot of these declines continue to happen.”

Waterways are critical lifelines for wildlife in dry places such as California, with a whole cascade of life depending on them. Droughts mean this lifeblood no longer flows through the landscape.

Caitlin Cornwall, a project manager at the Sonoma Ecology Center, says: “There is a direct link between reversing climate change and having more birds in Bernie’s recordings.

She calls Sugarloaf “a relatively mid-range example of what happens when you have an extreme drought”.

The drought is not the only pressure. Across the state, human activity is cutting into animal food sources and habitats. Wild places are being converted into farmland and urban areas, and invasive species are becoming more common. Some of the songbirds Krause captured in 1993, such as the orange-crowned warbler, are now in widespread decline.

Many of the birds captured in Krause’s recordings are migrant species “living on a knife-edge”, says Cornwall. “If a year’s cohorts have died in a particular place, then next year the young – and even the adults – might not come back.” It could take generations for them to recolonise a habitat – assuming they survive elsewhere.

Krause, who has been recording ecosystems from Africa to Latin America to Europe, says it is depressing to hear how the places he visits have changed. His personal library contains more than 5,000 hours of recordings, taken over 55 years from all over the world. He estimates that 70% of his archive is from habitats that have now disappeared.

“The changes are profound,” he says. “And they are happening everywhere.”

“I’ve got to this point in my life now where I just don’t know quite how to handle it, or how to express it, or what to say – yet I’ve got to tell people what I see and what I hear. Actually, I don’t need to say anything – the messages are revealed through the soundscapes.”

There have been some optimistic signs at Sugarloaf Ridge. Roney has 40 cameras around the park, which have taken 60,000 photos in the past five years. He says there are hopeful indications, such as black bears and mountain lions moving into the area. Krause is 85 now and says his hearing days are numbered: he is almost totally deaf in his right ear and has some hearing loss in his left. He can no longer hear subtle changes in sound like he used to. “That’s a loss that I quite regret but have learned to live with,” he says.

Still, he looks forward to spring and to his next recording in Sugarloaf Ridge. He is hopeful that this year there could be signs of a resurgence. “The stories conveyed through the voices of these critters will tell us all we need to know that’s worthwhile,” he says. “When we finally learn how to listen.”

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