(Nature sounds) 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 orchestra, that 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. The soundscape is made up of three basic sources. The first is the geophony, or 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. 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. 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 part. Fortunately, 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. 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 human noise, among many other 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. 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. 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 meters altitude, and 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 operation, I 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 top, lowest 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. (Nature sounds) Well, a year later I returned, and 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. (Nature sounds) Coming up is the sound of a woodpecker. 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 place, which would confirm the logging company's contention that there's nothing of environmental impact. However, our ears tell us a very different story. 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 Alaska, and 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 belly, and 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) At the end of its breeding cycle, the 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. (Frogs croaking) 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 1,100 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 human noise, even though 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 jet, the signature, is in yellow at the very bottom of the page. (Frogs croaking) Now at the end of that flyby, it took the frogs fully 45 minutes to regain their chorusing synchronicity, during which time, and under 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 frog populations, once diminishing during the 1980s and early '90s, have pretty much returned to normal. 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 it up, killing the female and her young babies. Horrified, 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. (Beaver crying) Yeah. Well. 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 habitat destruction. And where environmental sciences have typically tried to understand the world from what we see, a much fuller understanding can be got from what we hear. Biophonies and geophonies are the signature voices of the natural world, and as we hear them, we're endowed with a sense of place, the true story of the world we live in. In a matter of seconds, a soundscape reveals much more information from many perspectives, from quantifiable data to cultural inspiration. Visual capture implicitly frames a limited frontal perspective of a given spatial context, while soundscapes widen that scope to a full 360 degrees, completely enveloping us. And while a picture may be worth 1,000 words, a soundscape is worth 1,000 pictures. And our ears tell us that the whisper of every leaf and creature speaks to the natural sources of our lives, which indeed may hold the secrets of love for all things, especially our own humanity, and the last word goes to a jaguar from the Amazon. (Growling) Thank you for listening. (Applause)
(大自然的聲音) 我第一次開始錄野外聲境 是 45 年前 那時候我不知道原來螞蟻 昆蟲幼體、海葵及病毒 都會產生獨特的音調 但牠們確實會 地球上的每一個 野生棲地也是如此 就像從我背後聽到的亞馬遜雨林 事實上,溫帶及熱帶雨林 都會產生活力四射的動物樂團 這種即席卻組織化的表演 集合了昆蟲、爬行類、 兩棲類、鳥類和哺乳類動物 而每一種野生棲地流瀉出的聲境 都有自己的特徵 其中所含的資訊多到令人難以置信 而我今天要與各位分享的 就是其中的一部分 聲境有三種基本來源 第一是地形聲響 或稱非生物聲音 在任何棲地都會產生 像樹上的風,溪裡的水 岸邊的海潮,地球的活動 第二種稱作生物聲響 生物聲響是指 特定棲地上的生物 在某時某地產生的聲音 第三種則是我們人類產生的所有聲音 稱為人的聲響 有些可受控制,像音樂或戲劇 但大多數為混亂而不連貫 有些人就稱之為噪音 曾有一段時間我認為野外聲境 毫無價值 它們擺在那兒,形同虛設 但我錯了。我從這幾次邂逅中發現 仔細聆聽為我們提供了極有價值的工具 可以評估一個棲地上 所有生物的健康狀態 當我在 60 年代晚期開始錄音 普通的錄音法所能錄到的聲音 只能捕捉到個別物種的片段 一開始的時候最主要是鳥類 但後來就有像哺乳類或兩棲類等動物 對我而言,這有點像是試著去瞭解 貝多芬的第五號交響曲的偉大 卻只聽單一小提琴的聲音 而不管整個樂團的表現 而且只聽那個部分 所幸,有愈來愈多的機構 使用更全方位的機型 是我和幾個同事引進 聲境生態學領域的 我在四十年前開始錄音時 可以只錄 10 小時 就得到一小時的可用材料 夠我做一張唱片或影片配樂 或給博物館做裝置藝術 現在,因為全球暖化 資源開採 人類噪音以及其他很多因素 要錄到一千小時以上 才能取得同等量的東西 我存檔中有 50% 錄自受到劇烈改變的棲地 這些地方不是變成全然無聲 就是再也聽不到原有的聲境 棲地評估的常用方法 就是以肉眼計算某面積內的物種數量 以及每種物種的個體數量 不過我能以比較我們所聽到 結合了密度及多樣性的數據 得到更精確的棲地健康報告 而我想讓大家看一些例子 代表了探究這片天地 所顯示出的潛在價值 這裡是林肯草原 林肯草原位於舊金山以東 開車三個小時半的內華達山脈 海拔約二千公尺 我已經在那裏錄了很多年 1988 年有個林業公司說服當地居民 說絕對不會有任何環境影響 因為他們正在試用新的方法 稱為「等級伐採」 就是這裡砍一棵那裡砍一棵 而不是皆伐整片區域 我得到許可 能在開工前及開工後錄音 我把器材架好<br/>錄到了大量的清晨鳥叫聲 錄音及校準條件非常嚴格 因為我想要一條非常好的基線 這是聲音頻譜分析的例子 聲音頻譜分析把聲音用圖像表示 時間軸從頁面的左到右 這個例子畫了 15 秒 頻率軸從頁面的下到上 從最低到最高 你可以看到一條小溪的音調 呈現在頁面下方三分之一處 而那片草地原有的小鳥 其音調則在頁面上方出現 那裏曾有很多小鳥 這是林肯草原在等級伐採前的聲音 (大自然的聲音) 但是一年之後我回去 在同樣的設定條件 同樣的狀態下錄音 我錄了幾個範例 同樣是清晨鳥叫聲 而這是我們現在所得到的 這是等級採伐之後的狀態 你可以聽見小溪依然呈現在 頁面的下方三分之一處 但是注意一下頁面上方 三分之二處缺了什麼 (大自然的聲音) 馬上要出現的是啄木鳥的聲音 嗯,過去 25 年內我陸陸續續 去了林肯草原 15 次 而我可以告訴你生物聲響 那裡的生物聲響密度及多樣性 還沒有恢復到 開工前的狀態 但這是林肯草原在開工後的照片 而你可以看見從照相機的角度 或說從人眼的角度 很難發現有哪根枝哪棵樹不見了 這可以證實這家伐木公司的論點 就是沒有環境影響 然而我們的耳朵聽到的 卻完全不是這麼回事 年輕的學生總是要問我 這些動物在說什麼 而我是真的不知道 但我可以告訴你牠們的確會表達自己 我們瞭解與否則是另外一回事 有一次我沿著阿拉斯加的海岸行走 我遇到了這個退潮後的小潮池 裡面佈滿了一群海葵 這些奇妙的捕食機器 珊瑚及水母的親戚 我很好奇想看看牠們會不會發出聲音 所以我垂吊了一個水聽器下去 是一種水下麥克風,以橡膠包住 才降到海葵口盤處 這些小怪物立刻開始 把麥克風吸入肚子裡 而且觸手就在麥克風表面上尋找 有營養價值的東西 這種像靜電的聲音非常低頻 你們馬上就會聽到 (靜電聲音) 對!但聽!當牠找不到東西可吃 (喇叭聲) (笑聲) 我認為這種表達法是大家都能理解的 共通語言 (笑聲) 在繁殖週期尾聲 大盆地鋤足蟾 會在地表下一公尺處挖一個洞 在這種硬梆梆的美西沙漠土壤裡 牠可以在那裡待上好幾個季節 直到環境又合適了才出來 當土地的水分足夠了 春天時,青蛙會在地表挖洞 聚在這些又大又生氣盎然的池子旁邊 數量很大 而且牠們發聲合唱 彼此之間絕對同步 牠們如此做有兩個原因 第一是為了競爭 因為牠們在尋找交配對象 第二是為了合作 因為如果牠們同步發聲 天敵如土狼、狐狸、貓頭鷹等 很難從中挑出單隻當飯吃 這是青蛙合唱的聲音頻譜分析的樣子 在生態條件非常健康的狀態下 (青蛙呱呱叫) 莫諾湖就在優勝美地國家公園東方 位於加州 這裡是這些蟾蜍最愛的棲地 同時這裡也是美國 海軍戰鬥機駕駛的最愛 他們在這裡訓練飛行員以時速 超過一千一百公里的速度駕駛飛機 但飛行高度只距 莫諾盆地地表數百公尺 非常快非常低而且很大聲 所以這些人的聲響,人類的噪音 即使遠在六公里半以外 就是距離那個你剛剛聽到的青蛙池塘 這些噪音也能把 蟾蜍大合唱的聲音給蓋掉 你可以看見在這個聲音頻譜分析裡 本來在第一個聲音頻譜分析圖 上端的能量都不見了 而合唱在兩秒半 四秒半及六秒半都中斷了 然後噴射機的聲音,這個音頻 在頁面最下面以黃線畫出 (青蛙呱呱叫) 那麼在定點飛行結束後 這些青蛙要花整整 45 分鐘 才能重現同步合唱 在這段期間,在大滿月下 我們觀察到有兩隻土狼及一隻大雕鴞 跑來抓了幾隻走 好消息是因為棲地復原了一點點 飛行訓練也少了一點 這些青蛙的總數 本來在 1980 年間及 90 年代早期減少的 現在已經恢復得差不多了 我想以一隻河狸說的故事來結尾 這是個非常悲哀的故事 但確實描繪了動物 有時候也有情感表現 這在老一輩的生物學者間 是非常具爭議的題目 我有個同事在美國中西部 一個池塘附近錄音 大概是在一萬六千年前 上一個冰河時期末時形成的 池塘的一部分也是河狸水壩 在一端維持整個生態系 非常微妙的平衡 有一天下午他在錄音 突然不知道從哪兒冒出 一對狩獵監督官 他們並沒有什麼明顯的理由 就走到那座河狸水壩 丟了一根炸彈下去把它炸了 弄死了一頭雌河狸及幾隻小河狸 我的同事嚇壞了躲著不敢出來 試著整理情緒 並繼續記錄那天下午 還能錄到的東西 到了晚上,他捕捉到了 一個令人動容的畫面 孤單倖存的雄河狸緩慢的游泳繞圈圈 傷心欲絕地哀哭著牠失去的妻小 這大概是我所聽過 從生物口中發出最令人難過的聲音了 無論是從人類或動物的口 (河狸哭泣) 是啊,唉! 聲境有很多面 其中還有動物教我們跳舞唱歌 這部分我下次再說 但你已經聽到生物聲響如何 幫助我們更清楚地了解大自然世界 你也已經聽到資源開採 人類噪音以及棲地破壞的影響 環境科學通常 試著以肉眼所見來了解這個世界 但從耳朵所聽到的 能讓我們有更全盤的了解 生物聲響及地形聲響是 自然世界的招牌聲音 我們一聽到這些聲音 就會對這地方產生感覺 是我們所處的世界的真實故事 就在彈指之間 聲境透露出的資訊 比其他面向更多 從可量化的數據到文化靈感都可以 視覺只能隱約捕捉到 從正面角度看某空間範圍的樣子 但聲境把視角擴大 變成 360 度,完全包圍我們 而一張照片或許值一千字 一份聲境數據卻值一千張照片 而我們的耳朵告訴我們 每片葉子每種生物的細微聲響 都是我們生活中的自然資源在說話 而這確實可能解釋萬物愛的奧秘 尤其是我們人類本身的愛 以及,最後是亞馬遜美洲虎要說話 (吼叫聲) 謝謝大家聆聽 (掌聲)