Unfortunately, natural habitats are being annihilated at an increasing pace. There are several tremendously significant ramifications.

This month's installment of "Sound Matters" is indebted to the life and work of Bernie Krause, one of the foremost bioacousticians and an environmental hero who has traveled the world recording the sounds of creatures and natural habitats. This article is based on a speech delivered at the San Francisco World Affairs Council on January 31, 2001 ((C) 2001, Wild Sanctuary, Inc.), which I came upon in the Spring 2002 issue of Earth Island Journal (which may still be available at your favorite retail outlet).

The human dimensions of ecology are profound and wide-ranging. The late Dr. Paul Shepard, in his book, Nature and Madness, relates the loss of wild habitat and our connection to the natural world with political, economic and social aspects of our own culture and our lives in general. Canadian composer author R. Murray Shafer coined the word "soundscape." His classic book entitled Tuning of the World had a great impact on my own life; I highly recommend that you read this as well as Bernie Krause's new book, Discovering the Voice of the Natural World.

Krause writes: Through my field work, I discovered that in undisturbed natural environments, creatures vocalize in relationship to one another much like instruments in an orchestra. On land, this delicate acoustic fabric is almost as well defined as the notes on a page of music when represented graphically in the form of "voice prints."

For instance, in healthy habitats, certain insects occupy one sonic zone of the creature bandwidth, while birds, mammals, and amphibians occupy others where there is no competition. This system has evolved so that each voice can be heard distinctly and each creature can thrive as much through its iterations as any other aspect of its being.

This biosymphony, or "creature choir," serves as a vital gauge of a habitat's health. But it also conveys data about its age, its level of stress, and valuable information such as why and how creatures in both the human and nonhuman worlds have learned to dance and sing.

Yet, this miraculous biosymphony--this concert of the natural world--is now under serious threat ... giving new meaning to the phrase "silent spring" (and summer, fall and winter, as well.)

Nature's fragile weave of sound is being torn apart by three main factors: the incredible amount of noise humans make; our lust for precious natural resources; and by a seemingly boundless need to conquer aspects of our natural world rather than to find a way to abide in consonance with them.

It is a recipe for tragedy. Evidence of the damage from these noise factors has only recently become known. Bioacoustic field research techniques have revealed patterns that confirm the loss that those of us par-ticularly sensitive to the natural world have instinctively been feeling for a long time.

Here's just one example. 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 protectively expansive audio performance inhibiting predators from locating any single place from which sound emanates. The synchronized frog voices originate from so many places at once that they appear to be coming from everywhere.

However, when the coherent patterns are upset by the sound of a jet plane as it flies within earshot of a pond, the frog biosymphony 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.

(This information should be part of every grade school nature class!)

The introduction of noise into natural soundscapes increases stress for both humans and non-human species alike, even though its human victims may not seem conscious of the effect. Let me give you another example. Science News reported on an experiment done on humans in France in the early l980s that exposed sleeping subjects to l5 nights' worth of recorded traffic noise. A variety of instruments were used to measure stress. After two to seven nights, the subjects reported that they were no longer dist-urbed by the noise. i.e., they claimed they had become "used to it." However, when scientists checked their readings, they found that their subjects' stress levels were identical to those logged the first night.

(Think about the implications of this fact. You may want to clip this and show it to noisy neighbors or others who make fun of your greater sensitivity to sound. When I reported this in my l985 book, Sound Health, I had hoped it would be picked up by the national media. It wasn't, and still hasn't been ... but I think we may be approaching a critical mass of mass consciousness.)

Natural soundscapes cannot be replaced. These are habitats that no one will ever be able to hear again. They are forever silenced or hopelessly altered.

Without our link to nature, a fundamental piece of the fabric of life is sadly compromised. Before the forest echoes die, we may want to listen carefully to the natural soundscapes that still abide. When we do, we'll discover that we aren't separate, but a vital part of one fragile biological place.

This divine music is fast growing dim. The whisper of every leaf and creature implores us to cherish the natural sources of our lives which may hold secrets of love for all living things, especially our own humanity.

Thank you, Bernie. For more information and some fascinating sound samples, visit him at www.wildsanctuary.com. His new book / CD-ROM is Wild Soundscapes: Discovering the Voice of the Natural World (800-443-7227