Bernie Krause, chirp@wildsanctuary.com
Wild Sanctuary, Inc.
13012 Henno Rd.
Glen Ellen, CA 95442
Popular version of paper 3aNS2
Presented Wednesday morning, November 3, 1999
138th ASA Meeting, Columbus, Ohio
In his important book, Nature & Madness (Sierra Club Books, 1982), the late Paul Shepard wrote that the increased signs of pathological human behavior in Euro-American culture are directly related to the loss of wild habitat and our connection to the natural world. One of the most important resources of the natural world is its voice - - or natural soundscape. In its pure state, where no human noise is present, natural soundscapes are glorious symphonies. However, the combination of shrinking habitat coupled with an increase of human noise has created conditions where non-human communication necessary to creature survival has been cut off. At the same time, humans are denied an experience of the wild natural essential to theirs.
In undisturbed natural environments, creatures vocalize in relationship to one another very much like instruments in an orchestra. On land, in particular, this delicate acoustic fabric is almost as well-defined as the notes on a page of music. C ertain insects occupy one sonic zone of the creature band, and birds, mammals, and frogs occupy others not yet taken and where there is no competition. That is so each voice can be heard distinctly and each creature can thrive. The same type of event also occurs in certain marine environments. This biophony, or animal chorus, serves as a vital gauge of a habitat's health, its age, its level of stress, and provides us with an abundance of other valuable new information such as why and how creatures have learned to sing. Yet, this miraculous biophony is under siege.
The fragile weave of sound just described is being torn apart mainly by two forces: the incredible noise we humans make, and by our undiminished lust for precious natural resources. For example, when I first began recording in 1968, it would take about fifteen hours to capture one hour of usable material for a tape or CD. Now it takes nearly two thousand hours to capture the same amount of sound. Compare that to 45 percent of our undisturbed forests still standing in 1968 where now less than 2 percent are left only 32 years later. This staggering observation, combined with the sound of chain saws, snowmobiles, ATVs, trail bikes, jet skis, deep-throated boat engines pulling ever faster water craft around otherwise pristine lakes, has created a recipe for tragedy unless we are willing to make an immediate shift in our view of the need for mechanical toys.
Evidence of the damage from these factors has only recently come to light. As a result of the field of bio-acoustics - - the study of the sound of living organisms and habitats, patterns are beginning to appear through the use of new field research techniques that confirm the loss those of us particularly sensitive to the natural world have been instinctively feeling for some time. The following examples demonstrate the point:
Many types of frogs and insects vocalize together in a given habitat so that no one individual stands out among the many. This chorus creates a protective audio screen thwarting predators from locating where the sound is coming from. The synchronized frog voices originate from so many places at once that it appears to be coming from everywhere. However, when the coherent patterns are upset by the sound of a jet plane as it flies within range of the pond, the special frog biophony is broken. In an attempt to reestablish the unified rhythm and chorus, individual frogs momentarily stand out giving predators like coyotes or owls perfect opportunities to snag a meal. While recording the rare spade foot frogs above the north shore of Mono Lake in the Eastern Sierras one spring, a similar event actually occurred. After the jet disappeared, the forty-five minutes passed before the frogs were able to reestablish their protective chorus. In the dusk light we saw two coyotes and a great horned owl feeding by the side the small pond. Because of the unique manner by which we record and measure sound, we have discovered that the relatively intense sound produced by a low-flying jet airplane can cause changes in the biophony that make certain creatures to lose the life-saving protection of their vocal choruses.
Once, while doing acoustic research in the Amazon Basin, a multi-engine military jet flying low over the jungle interrupted the dawn chorus of birds and insects at a particular site where we were recording. When we returned to our lab and examined the effect of the jet noise on the natural soundscape, we found that the disruption caused by the jet caused many creatures to stop vocalizing while others altered their patterns. The momentary break in the integrity of the animal chorus created by the jet left open the strong possibility that many creatures would become victim to opportunistic predators such as hawks or resident mammals.
Because of the noise introduced into their environment by cruise boats traveling in Glacier Bay, humpback whales have been seen trying to swim away and hide from the noise, ducking behind spits of l and or behind large blocks of ice that had broken off glaciers apparently in an effort to get into quieter noise "shadows". Where once there were many, in recent years, fewer and fewer whales have been seen in the Bay. Along with other factors, i t is believed by some biologists that human-induced noise is a major contributing ingredient to the falling numbers.
The loss of natural soundscape diminishes human experience of the wild while human noise increases stress. Keeping in mind that human and non-human species respond differently to types, loudness, or combinations of mechanical or human noises, we are just now beginning to understand that many of these sounds introduce affliction in both worlds. An experiment done on humans in France invited subjects to adapt to sleeping in the laboratory. After an initial few nights of quiet, the subjects were then subjected - - while asleep - - to fifteen nights worth of recorded traffic noise. The sleeping subjects were wired to instruments used to measure stress. "Heart rate, finger-pulse amplitude, and pulse-wave velocity were measured throughout the night, and each sleeper filled out a questionnaire upon waking." Two to seven nights later, the subjects reported that they were no longer disturbed by the noise (e. g. they thought that they had become used to it). However, the stress effects - - heart rate, etc. "measured the fifteenth night were identical to those logged the first." (Science News,121, June 5, 1982. 380)
There are many important reasons to reconsider the value of natural soundscape as a resource. For one thing, it is clear that naturalsoundscape cannot be replaced. Yet, there are rays of hope. We are beginning to understand late in the game that pristine natural soundscapes are reserves and resources critical to our enjoyment, understanding, and awareness of the natural wild. Without them, a fundamental piece of the fabric of life is sadly compromised. That is why the National Park Service recently implemented a strong educational and administrative plan to protect natural soundscapes. They have been positioned not only as a major resource, but as one of great value worth preserving for visitors and creatures, alike. Visitor reaction to all the noise in the national parks convinced the administration of the parks that it is important to attempt to hear and treat soundscapes differently - - as important to our well-being and health as the preservation of pure fresh water, clean air, and non-polluted soil. If the NPS succeeds in its effort to convince the visiting public of this idea, we will have come a long way toward our goal of delivering on our objective of responsive stewardship of the wild natural.
For the past quarter century, Dr. Krause has traveled the world capturing sounds of creatures and environments large and small. He has worked at the research sites of Jane Goodall (Gombe, Tanzania), Birute Galdikis (Camp Leakey, Borneo), and Dian Fossey (Karisoke, Rwanda), recording and evaluating the effects of ambient sound on the vocalizations of the great apes. He was also Scientific Director of the operation that rescued Humphrey the humpback whale from the Sacramento Delta (1985) using processed feeding sounds of the same species to lure him to the ocean. Aside from his work in bio- acoustics, Dr. Krause also has a background in music having replaced Pete Seeger in The Weavers (1963), introduced and contributed synthesizer performances to over 135 major feature films including, Apocalypse Now, and over 250 recordings with major musical acts. Through his company, Wild Sanctuary, he has recorded 50 environmental record albums and creates interactive environmental sound sculptures for museums, zoos, aquaria and other public spaces. His latest book, INTO A WILD SANCTUARY, Heyday Press, 1998) explains the road to the discovery of biophony . More information can be found on the Wild Sanctuary web site: www.wildsanctuary.com