Martyn Stewart: The David Attenborough of sound

Recording animals in their natural habitat is not a job for those who lack patience.

Capturing just 20 seconds of a songbird's chirrup, or an elk's bugle, or a kangaroo's chortle often requires hours of stillness and solitude.

It's a craft that Birmingham-born sound recordist Martyn Stewart has perfected over the last 55 years.

In that time, he's built up one of the largest private collections of natural sound in the world. Comprising 30,000 hours of material, it includes recordings of 3,500 bird species, alongside countless mammals, insects, amphibians and reptiles, as well as soundscapes of the Serengeti, the Arctic and Chernobyl, 10 years after the nuclear reactor meltdown.

At least four of the species he's recorded are now extinct in the wild, including the northern white rhinoceros and the Panamanian tree frog.

Sitting still and keeping quiet is all part of the job, he says, but it isn't simply a test of endurance. It can also put you in grave personal danger - as he discovered on a trip to the Big Bend National Park in Texas.

"I was recording the morning soundscape when a mountain lion came up behind me and jumped at my head," he recalls.

"It thought I was easy prey because I was silent. It dived at my body. I punched it in the face and it ran off.

"It was an incident of about 20 seconds but I had 125 stitches from my ear around the back of my head."

Instead of reporting the incident to the park ranger he spun a story about falling down a steep bank and cutting his head open on a creosote bush.

"I didn't want to get the cat into trouble," he says.

When you spend time with Stewart, it's immediately apparent how deep his reverence for nature runs.

He talks about the species he's met with quiet admiration, pausing often to explain that being amongst wildlife is his "sanctuary".

"The dawn chorus is incredible," he marvels. "You have 50-plus species reading the news to each other. I interpret it as a conversation:

- 'Oh, where have you been?'

- 'I was down in Argentina.'

- 'What was the flight like?'

- 'Good. Have you met Joe next door?'"

Stewart traces his passion back to childhood. Born and raised in Birmingham, in the West Midlands, he was lucky enough to live on a council estate directly opposite a greenbelt site "that went on for miles and miles".

"There was a little clump of woods about a mile from the house where you would find badgers, hedgehogs, hoverflies and all kinds of birds.

"I used to go there and lay on my back and listen to all the sounds... and it just enthralled me."

As chance would have it, his elder brother was the singer in a band - so Stewart took his microphone, borrowed a reel-to-reel tape machine and made his first recording, of an Eurasian Blackbird.

"The blackbird was kind of like my friend," he says. "When it made an alarm call, you knew somebody was entering the woods. So I got to know all the calls and the different vocalisations and what they meant. And I still have that recording now at the age of 66."

Ever since, Stewart has been building an unparalleled collection of field recordings, visiting more than 55 countries and cataloguing 97,000 sounds. They've been used in natural history documentaries, as well as films and TV dramas.

Others have served a more political purpose: he helped expose the illegal slaughter of seals on Namibia's Skeleton Coast, after setting out to record the breeding colonies of the Cape Coast. Ignoring signs that said "trespassers will be shot", he was arrested by police who confiscated his equipment - but not before he swapped out the memory cards for blanks.

"So if it's a toss up between animals frightening me and human beings, I think it's the latter," he says.

More than anything, however, Stewart is the David Attenborough of bird call. He has documented almost every species in his adopted home of North America - and is so attuned to their melodies that he can pick out where different birds of the same species come from.

"The Red-Winged Blackbird, for instance, has this 'conk-la-ree' sound but they all have different ways of talking.

"It's like a Geordie talking to a Liverpudlian. Every state has a different accent - and yet the people in America all sound the same to me!"

Capturing these sounds is harder than you might think.

Over the years, Stewart has learned to eat a big breakfast in case the microphone catches his stomach rumbling; and he invests in industrial quantities of insect repellent, otherwise his recordings are spoiled by buzzing (and the occasional slap of palm against forearm - his love of nature doesn't extend to mosquitoes).

But the last decade has presented a bigger challenge - human interference.

"The environment we live in these days is incredibly noisy," he says. "We have seven billion people on the planet making a lot of noise. Here where I live, in the United States, there's 20,000 planes in the sky at any given time. Then you have horns and ATVs, leaf blowers, cell phone interference.

"Twenty years ago, if I was to record one pristine hour of sound, it would take about three or four hours to capture that with just minimal editing.

"Today, to capture that one hour takes about 2,000 hours. Such is the noise that we live in."

Stewart estimates that two-thirds of the environments he has recorded over the last half-a-century have now vanished forever.

"The roads that have gone through the Serengeti break the soundscape. A critical habitat has disappeared. Only 2% of old growth forests in the United States are left. And within those, you have forest dwellers like the spotted owl that are critically endangered. And so, so many more."

That's one of the reasons Stewart has decided to open up his archives, making albums of habitats that are under threat, or lost.

"You can't protect anything you don't understand, so I thought the best way to educate people about that was sound," he says.

Time is running out - in more ways than one. In December 2020, Stewart was diagnosed with bone cancer, and given three to five years to live. After further tests this year, the timeline was drastically shortened.

His niece, Amanda Hill, who worked on the BBC's Planet Earth, has been helping him prepare the recordings for release.

"I've found this project incredibly emotional," she says. "Martyn and I have been close forever and I was always mesmerised by these remarkable adventures he's been on.

"He made the natural world come to life in a way that nobody had ever done for me, and his curiosity was intoxicating.

"So when we found out that Martyn was sick… there was a real need to have a conversation about what would happen with this remarkable legacy that he'd created.

"He always believed there was an intrinsic love for the world around you when you're young, but somehow as the world crowds in, nature gets crowded out.

"And I think these sounds, for us, are a way of trying to share something beautiful and see if there's a way to inspire people to listen more intently and to connect more deeply.

"So yes, it's an incredibly emotional experience but the hope is that it inspires people to continue Martyn's work. We see it as a beginning."

"You know I'm not a talented guy," he says with typical humility. "The animals are the performers. I just sit there with a microphone and record them."

His hope is that the project "gives the animals a voice" and focuses our minds on "how precious their environment is".

But he also wants to share what the natural world gave him: sanctuary.

"You know, with this cancer that I have, I can walk over to the beach and sit down on the dunes and listen to the waves crashing - and it's incredible therapy.

"And I'm hoping that my sounds are maybe going to reach the people who need that."