You Can Actually Hear the Climate Changing

Bernie Krause’s vast library of field recordings reveals a sad truth: wild sounds are quickly vanishing

Krause in California’s Sugarloaf Ridge State Park. (Photo: Ian Allen)
Krause in California’s Sugarloaf Ridge State Park.

Soundscape ecologist Bernie Krause has recorded jaguars in the Amazon, ice in Antarctica, insects in Zimbabwe, rainstorms in Borneo, and orcas in the Pacific. The 77-year-old began studying nature’s sounds at age 30, later earning a Ph.D. in creative arts. (This was after two successful decades as a musician and producer.) He has since traveled to the world’s most remote areas to create an audio library that began as an inventory of the intricate symphonies unique to each ecosystem but has become a way to document biodiversity and, most recently, loss.

Krause’s archive now consists of 5,000-plus hours of what he calls “whole habitat” field recordings. To get them, he sets up a wind-protected microphone on a tripod, plugs it into a handheld recorder, and captures everything that occurs. More than half of the 3,700 habitats represented in the archive—from Yellowstone to Australia to his own backyard in Glen Ellen, California—are now either totally silent or severely diminished because of human activities like mining, logging, poaching, real estate development, airplane traffic, warfare, and climate change. Outside spoke to Krause shortly after the release of his new book, Voices of the Wild: Animal Songs, Human Din, and the Call to Save Natural Soundscapes, to discuss how wild sounds allow us to examine changes that may otherwise go unnoticed—and whether they might be on the verge of vanishing forever.

OUTSIDE: What is soundscape ecology?
KRAUSE: Most of our writing and thinking about the natural world is visual. If it looks pretty, if it’s visually spectacular, that’s what we concentrate on. We have the descriptive language for that kind of reflection. But we have few words to describe in any great detail the sounds we hear when walking in the woods. Soundscape ecology is, in part, a response to this gap. It’s the study of the sound that comes from the landscape—urban, rural, or wild. I concentrate on the organisms in remote and still-untrammeled places. I call this the biophony: all the living organisms that vocalize in a given habitat, sounding together. There’s also natural sound in a habitat from wind in the trees and water in a stream. I refer to these nonbiological sounds as the geophony. 
In your new book, you point out that these biophonies provide us with “numerous prisms through which to view our relationship to the non-human critter world.” 
It’s so important that we begin to investigate these prisms and explore what they have to teach us—and soon. The natural soundscape is very fragile, and it’s disappearing very quickly. 

Which sounds are the first to go?
Usually, it’s what’s called partitioning. In a healthy habitat, insects, amphibians, reptiles, birds, and mammals form acoustic niches, sonic territories that they establish so that their voices can be heard unimpeded by others. These partitions are critical to their survival. Their cohesion begins to break down in habitats that are stressed even in slight ways. 

For example, there are logging companies that believe selective logging projects will have almost no environmental impact; you’re just taking out a tree here and there. But if you pay attention to the sounds of the living organisms inhabiting a given site, another story will often emerge. If you can get a baseline recording before the selective logging takes place, and then a follow-up recording after the first cuts have been made, you’ll likely hear some notable changes. 

What impact has the drought had on the biophony around your home in California?
There was absolutely no birdsong this past spring or summer in Valley of the Moon, in Sonoma County. There were birds, and there were a few calls, but no song. 

You’ve spent a significant amount of time recording in this area, especially at Sugarloaf Ridge State Park. 
I first recorded at Sugarloaf in 1994. It’s a 20-minute drive from my home, so it’s convenient and can be accessed spontaneously. Also, I wanted to measure the dynamic equilibrium of the site—the range of its biophonic expression with regard to density and diversity—over the course of the spring season. When I didn’t feel like taking extended trips abroad, I could still record at this spot, which I grew to love.
What changes have you observed there over the past 20 years? 
Most of my recordings at Sugarloaf have been done in March and April, at dawn, when it’s quite cool—typically in the low thirties. I usually set up just before nautical twilight, when it’s still dark on the ground but the horizon is pretty well outlined by the coming light. There’s no wind at that hour. The only sound is the stream, which flows through the landscape some 50 yards from where I typically record. Normal rainfall in the area is around 30 inches per year; the past four years we’ve been averaging fewer than eight. When the stream has no water because of that lack of precipitation, the stillness is eerie and a bit disconcerting.

In 2004, when the stream was running fully charged, the biophony was comprised of birdsong from dark-eyed juncos, golden-crowned and white-crowned sparrows, California towhees, acorn woodpeckers, black-headed grosbeaks, American robins, Brewer’s sparrows, red-shouldered hawks, pileated woodpeckers, and wild turkeys. Between 2009 and 2015, under the full impact of the drought, you hear an almost complete lack of density and diversity. Whether or not it regains vitality remains to be seen. It’s a true narrative, telling us that something is desperately wrong. 

Do you think the soundscape can recover?
It’s always in a state of flux. That’s why you will never hear the same kind of recording more than once. I’m coming to believe that no matter what we humans do, something will manage to adjust and survive. It probably won’t be us, though.

The Changing Soundscape

Costa Rican Forest

Measuring the consequences of clear-cutting on the Osa Peninsula

  • This is my first recording form the Osa Peninsula of Costa Rica, when the tropical forest had not yet been clear-cut.
  • After the site was clear-cut, the density and diversity of the biophony dropped off, showing the extreme stress on that habitat.

Fijian Reef

Recording the sound of a dying reef near the island of Vanua Levu

  • We recorded two sections of coral reef: one alive, and one dead. This portion of the reef was still healthy. We recorded 11 different species of fish and one snapping shrimp.
  • About 400 yards away, the same reef was already bleached and dying from ocean warming, acidification, and pollution. We found no fish living here.

Californian Meadow

Documenting the impact of selective logging in Lincoln Meadow in California's Sierra Nevada mountains

  • The first recording was made in June before selective logging began. We had been told that the logging would not affect the environment; we made this baseline recording with permission.
  • We recorded this clip exactly one year later. It shows that the biophony dropped off significantly. I've returned to Lincoln Meadow 15 times over the last 25 years and the biophony has yet to recover.

Support Outside Online

Our mission to inspire readers to get outside has never been more critical. In recent years, Outside Online has reported on groundbreaking research linking time in nature to improved mental and physical health, and we’ve kept you informed about the unprecedented threats to America’s public lands. Our rigorous coverage helps spark important debates about wellness and travel and adventure, and it provides readers an accessible gateway to new outdoor passions. Time outside is essential—and we can help you make the most of it. Making a financial contribution to Outside Online only takes a few minutes and will ensure we can continue supplying the trailblazing, informative journalism that readers like you depend on. We hope you’ll support us. Thank you.

Contribute to Outside
Filed To: NatureCalifornia
Lead Photo: Ian Allen
More Adventure