(Nature sounds)
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When I first began recording wild soundscapes 45, years ago I had no idea that ants insect larvae,,, Sea anemones and viruses created a sound signature. But they do. And so does every wild habitat on the planet like the,, Amazon rainforest you 're hearing behind me. In fact temperate and, tropical rainforests each produce a vibrant, animal orchestraThat instantaneous and organized expression of insects reptiles amphibians birds,,, and mammals. And every soundscape that. Springs from a wild habitat generates its own unique signature one that, contains incredible amounts, of information and. It 's some of that information I want to share with you today.
1: 08 The soundscape is made up of three basic sources. The. First is, the geophonyOr the nonbiological sounds that occur in any given habitat like wind, in the trees water in, a stream waves at, the ocean. Shore movement of, the Earth. The second of these is the biophony. The biophony is all of the sound that 's generated by. Organisms in a given habitat at one time and in one place. And the third is all of the sound that we humans generate that s. ' Called anthrophony.Some of it is controlled like music, or theater but most, of it is chaotic, and incoherent which some of us refer to as. Noise.
1: 54 There was a time when I considered wild soundscapes to be a worthless artifact. They were just there but they,, Had no significance. Well I was, wrong.What I learned from these encounters was that careful listening gives us incredibly valuable tools by which to evaluate. The health of a habitat across the entire spectrum of life.
2: 17 When I began recording in the late '60s the typical, methods. Of recording were limited to the fragmented capture of individual species like birds mostly in the beginning,,But later animals like mammals and amphibians. To me this was, a little like trying to understand the magnificence of Beethoven s. ' Fifth Symphony by abstracting the sound of a single violin player out of the context of the orchestra and hearing just that. One, Fortunately part.More and more institutions are implementing the more holistic models that I and a few of my colleagues have introduced. To the field of soundscape ecology.
3: 04 When I began recording over four, decades ago I could record for 10 hours and capture. One hour of usable material good enough, for an album or a film soundtrack or a museum installation. Now because of, global. Warming.Resource extraction and noise, human, many other, among factors it can take up to 1 000 hours, or more to capture the same. Thing. Fully 50 percent 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.
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.The usual methods of evaluating a habitat have been done by visually counting the numbers of species and the numbers of. Individuals within each species in a given area. However by comparing, data that ties together both density and diversity. From what, we hear I 'm able to arrive at much more precise fitness outcomes.And I want to show you some examples that typify the possibilities unlocked by diving into this universe.
4: 15 This is. Lincoln Meadow. Lincoln Meadow 's a three-and-a-half-hour drive east of San Francisco in the Sierra, Nevada Mountains at. About 2 000 altitude and, meters, I 've been recording there for many years, In 1988.A logging company convinced local residents that there would be absolutely no environmental impact from a new method they. Were trying called "selective logging," taking out a tree here and there rather than clear-cutting a whole area. With permission. Granted to record both before and after, the operationI set up my gear and captured a large number of dawn choruses to very strict protocol and, calibrated recordings because. I wanted a really good baseline. This is an example of a spectrogram. A spectrogram is a graphic illustration of sound with. Time from left to right across the page - 15 seconds in this case is represented - and frequency from the bottom of the. Page to, the topLowest to highest. And you can see that the signature of a stream is represented here in the bottom third or half of the. Page while birds, that were once in that meadow are represented in the signature across the top. There were a lot of, them. And here 's Lincoln Meadow before selective logging.
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(Nature sounds)
, 5: 44 Well a year later, I returnedAnd using the same protocols and recording under the, same conditions I recorded a number of examples of the same dawn. Choruses and now, this is what we 've got. This is after selective logging. You can see that the stream is still represented. In the bottom third of, the page but notice what 's missing in the top two thirds.
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(Nature sounds)
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Coming up is. The sound of a woodpecker.
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.Well I ', ve returned to Lincoln Meadow 15 times in the last 25 years and I, can tell you that the biophony the density,, And diversity of that biophony has not, yet returned to anything like it was before the operation. But here 's a picture. Of Lincoln Meadow, taken after and you can see that from the perspective of the camera or the, human eye hardly a stick. Or a tree appears to be out, of placeWhich would confirm the logging company 's contention that there' s nothing of environmental impact. However our ears, tell. Us a very different story.
6: 59 Young students are always asking me what these animals, are saying and really I 've got no. Idea. But I can tell you that they do express themselves. Whether or not we understand it is a different story. I was walking. Along the shore, in AlaskaAnd I came across this tide pool filled with a colony of, sea anemones these wonderful eating machines relatives of, coral. And jellyfish. And curious to see if any of them made any noise I dropped, a hydrophone an underwater, microphone covered. In rubber down the, mouth part and immediately, the critter began to absorb the microphone into, its bellyAnd the tentacles were searching out of the surface for something of nutritional value. The static-like sounds that are. Very, low that you 're going to hear right now. (Static sounds), Yeah but watch. When it didn' t find anything to eat - (Honking. Sound) (Laughter) I think that 's an expression that can be understood in any language. (Laughter)
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At the end of its. Breeding, cycleThe Great Basin Spadefoot toad digs itself down about a meter under the hard-panned desert soil of the, American West where. It can stay for many seasons until conditions are just right for it to emerge again. And when there 's enough moisture in. The soil in, the spring frogs will dig themselves to the surface and gather around, these large vernal pools in great numbers.And they vocalize in a chorus that 's absolutely in sync with one another. And they do that for two reasons. The first is. Competitive because, they 're looking, for mates and the second, is cooperative because if they' re all vocalizing in sync. Together it makes, it really difficult for predators, like coyotes foxes and owls to single out any individual for a meal.This is a spectrogram of what the frog chorusing looks like when it 's in a very healthy pattern.
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(Frogs croaking)
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Mono. Lake is just to the east of Yosemite National Park, in California and it 's a favorite habitat of these toads and it, s also.' Favored by U.S. Navy jet pilots who train, in their fighters flying them at speeds, exceeding 1100 kilometers an hour and altitudes only a couple hundred meters above ground level of the Mono Basin very fast very,,, Low and so, loud that the anthrophony the noise, human, though even it 's six and a half kilometers from the frog pond you. Just heard a, second ago it masked the sound of the chorusing toads.You can see in this spectrogram that all of the energy that was once in the first spectrogram is gone from the top end. Of, the spectrogram and that there 's breaks in the chorusing at two and, a half four and a half and six, and a, half seconds. And then the sound of the, signature jet the, in is yellow at the very bottom of the page.
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(Frogs croaking)
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Now. At the end of, that flybyIt took the frogs fully 45 minutes to regain their chorusing synchronicity during time, which, under and a, full moon we. Watched as two coyotes and a great horned owl came in to pick off a few of their numbers. The good news is that with a,, Little bit of habitat restoration and fewer flights the populations, frog, diminishing once during the 1980s and early ', 90sHave pretty much returned to normal.
10: 51 I want to end with a story told by a beaver. It 's a very sad story but it, really. Illustrates how animals can sometimes, show emotion a very controversial subject among some older biologists. A colleague. Of mine was recording in the American Midwest around this pond that had been formed maybe 16 000 years, ago at the end of. The last ice age.It was also formed in part by a beaver dam at one end that held that whole ecosystem together in a very delicate, balance. And one afternoon while he, was recording there suddenly, appeared from out of nowhere a couple of game wardens who for,, No, apparent reason walked over to the, Beaver Dam dropped a stick of dynamite down it blowing up killing, it, the female. And her young, Horrified babies.My colleagues remained behind to gather his thoughts and to record whatever he could the rest of the afternoon and that,, Evening he captured, a remarkable event: the lone surviving male beaver swimming in slow circles crying out inconsolably. For its lost mate and offspring. This is probably the saddest sound I 've ever heard coming from any organism human or, other.
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(Beaver. Crying 12: 33)
.Yeah. Well.
12: 34 There are many facets to soundscapes among them, the ways in which animals taught us to dance, and sing. Which I 'll save for another time. But you have heard how biophonies help clarify our understanding of the natural, world. You 've heard the impact of resource extraction human noise, and ha.
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