
“Townsend’s Rocky Mountain Hare” in John James Audubon’s ‘The Quadrupeds of North America’ (1851–54) (via Biodiversity Heritage Library/Flickr)
Bernie Krause has listened to nature since 1968, and in his decades recording environmental noise has become attuned to its changes. Whether it’s the impact of logging on a forest’s din or the sonic significance of the return of a species once thought extinct, the sounds of a landscape can reveal details of its ecology.

Cover of ‘Voices of the Wild’ (courtesy Yale University Press)
Voices of the Wild: Animal Songs, Human Din, and the Call to Save Natural Soundscapes, published by Yale University Press, is a compact book about exploring changes in the environment through sound. It follows Krause’s 2013 The Great Animal Orchestra: Finding the Origins of Music in the World’s Wild Places, as well as a 2014 symphony based on that publication. Reflecting on his recordings from the 1960s to now, Krause said in a 2013 TEDGlobal talk, “fully 50% of my archive comes from habitats so radically altered that they’re either altogether silent or can no longer be heard in any of their original form.”
As with the Cornell Lab of Ornithology’s Macaulay Library, the world’s largest natural sound archive, recording the voices of individual animals and their soundscapes can preserve specific moments in biodiversity — and echo the impact of encroaching human development or other changes. Krause is a musician as well as a soundscape ecologist, and his interest in recording, which he does through his organization Wild Sanctuary, has taken him around the world to its most remote places. Based in California, he’s also listened to the landscape closer to home, studying how the drought has dampened the natural noise.
In conjunction with Voices of the Wild, Yale University Press is hosting online sound recordings, a few of which are below. They demonstrate how listening to nature’s noise can alert us to its growing silence.

Bernie Krause (photo by Tim Chapman)
At Lincoln Meadow in California’s Sierra Nevada mountains, Krause recorded both before and after selective logging in the late 1980s. The technique was intended to be less intense than clear-cutting; however, when he returned a year later, the “rich biophony” he’d originally heard — the diversity of animal sounds — “was now practically silent.” As he writes in Voices of the Wild, to “the human eye and to a camera, the landscape looks unchanged and would have supported the logging company’s sustainability contention. But the soundscapes tell a very different story.”
The biophony of Lincoln Meadow in June 1988, prior to selective logging:
The biophony of Lincoln Meadow in June 1989, after selective logging:
On the Osa Peninsula in Costa Rica, Krause listened to the effects of clear-cutting on an old growth forest. After seven years, he returned to a place that was characterized by logging roads rather than trees.
Osa Peninsula, Costa Rica, in 1989, prior to the clear-cutting:
Osa Peninsula, Costa Rica, in 1996, after clear-cutting:
Krause monitored the “bioacoustic” alterations in California’s Sugarloaf State Park through three recordings, taken in the same place in 2004, 2009, and 2014 with a different diversity of birds.
Not all of the soundscapes are dire; some can signal the return of a species thought vanished, such as the Wyoming toad heard by his colleague Martyn Stewart. Considered regionally extinct, the toad, Krause writes, “was not visually identified, the vocalization has yet to be confirmed (some thought it might be a Canadian toad [Anaxyrus hemiophrys]), and it has not been heard or recorded at that site since, to our knowledge. But these kinds of recordings demonstrate the potential unleashed when the fine detail of biophonies is examined.”
Bernie Krause’s Voices of the Wild: Animal Songs, Human Din, and the Call to Save Natural Soundscapes is published by Yale University Press and available from Amazon and other online booksellers.