How human noise affects ocean habitats | Kate Stafford

譯者: Helen Chang 審譯者: S Sung

In 1956, a documentary by Jacques Cousteau won

雅克·庫斯托 1956 年的紀錄片

both the Palme d'Or and an Oscar award.

同時榮獲金棕櫚獎和奧斯卡獎。

This film was called, "Le Monde Du Silence,"

電影片名為：「寂靜的世界」

or, "The Silent World."

或「沉默的世界」。

The premise of the title was that the underwater world was a quiet world.

名稱的前提是： 水下是個寂靜的世界。

We now know, 60 years later,

六十年後的今天我們明白

that the underwater world is anything but silent.

水下世界一點也不寂靜。

Although the sounds are inaudible above water

雖然在水面上聽不到聲音，

depending on where you are and the time of year,

但取決於在什麼時間點 以及你身處何處，

the underwater soundscape can be as noisy as any jungle or rainforest.

水底下可能像任何叢林 或熱帶雨林般吵雜。

Invertebrates like snapping shrimp, fish and marine mammals

諸如蝦之類的無脊椎動物、 魚類，以及海洋哺乳動物

all use sound.

都使用聲音。

They use sound to study their habitat,

牠們用聲音來研究棲地、

to keep in communication with each other,

彼此溝通、

to navigate,

導航，

to detect predators and prey.

以及偵測天敵和獵物。

They also use sound by listening to know something about their environment.

牠們也透過聲音來了解周遭的環境。

Take, for an example, the Arctic.

以北極為例，

It's considered a vast, inhospitable place,

被認為廣大而不宜人居，

sometimes described as a desert,

甚至有時被形容是荒漠，

because it is so cold and so remote

因它寒冷而遙遠，

and ice-covered for much of the year.

在大部分的月份裡被冰所覆蓋著。

And despite this,

儘管如此，

there is no place on Earth that I would rather be than the Arctic,

我寧願身在北極， 勝過地球的任何其他地點，

especially as days lengthen and spring comes.

尤其當春日白晝漸長時。

To me, the Arctic really embodies this disconnect

我認為北極真正體現了

between what we see on the surface and what's going on underwater.

迥異的水上和水下兩個世界。

You can look out across the ice -- all white and blue and cold --

放眼望去，藍白冷冷的冰面上

and see nothing.

什麼也看不見。

But if you could hear underwater,

但如果你聽得到水下的聲音，

the sounds you would hear would at first amaze

你先會驚奇，

and then delight you.

然後會雀躍。

And while your eyes are seeing nothing for kilometers but ice,

極目所見，延展數公里的 冰面上似無一物，

your ears are telling you that out there are bowhead and beluga whales,

但耳朵卻聽到了弓頭鯨、白鯨、

walrus and bearded seals.

海象和髯海豹存在的聲音。

The ice, too, makes sounds.

冰也會出聲；

It screeches and cracks and pops and groans,

當冰塊互撞、摩擦， 或當溫度、洋流、風向變化時，

as it collides and rubs when temperature or currents or winds change.

會尖叫、崩裂、彈跳和呻吟。

And under 100 percent sea ice in the dead of winter,

在冬天完全冰封的海面下，

bowhead whales are singing.

弓頭鯨在唱著歌。

And you would never expect that,

超乎我們的想像，

because we humans,

因為人類

we tend to be very visual animals.

往往非常依賴視覺。

For most of us, but not all,

雖非全部，但我們大多數人

our sense of sight is how we navigate our world.

靠著視力在世上行進。

For marine mammals that live underwater,

對生活在水下的海洋哺乳動物而言，

where chemical cues and light transmit poorly,

那裡的化學訊號傳導差， 光線又不好，

sound is the sense by which they see.

因此牠們倚賴聲音來感知。

And sound transmits very well underwater,

而水傳導聲音極佳，

much better than it does in air,

比空氣好太多了，

so signals can be heard over great distances.

所以距離雖遠仍聽得到信號。

In the Arctic, this is especially important,

這在北極尤其重要，

because not only do Arctic marine mammals have to hear each other,

因為北極的海洋哺乳動物 不僅必須彼此互聽，

but they also have to listen for cues in the environment

還要聽取環境的線索，

that might indicate heavy ice ahead or open water.

像是前方到底有著巨冰 還是一片開放的水域。

Remember, although they spend most of their lives underwater,

記住，雖大部分時間在水下生活，

they are mammals,

牠們仍是哺乳類動物，

and so they have to surface to breathe.

必須浮到水面上呼吸；

So they might listen for thin ice or no ice,

所以牠們得靠傾聽尋找 薄冰、無冰的地方，

or listen for echoes off nearby ice.

或偵聽附近冰塊的迴聲。

Arctic marine mammals live in a rich and varied underwater soundscape.

北極海洋哺乳動物生活在 富含各種水下音景的地方。

In the spring,

在春天可能是混音。

it can be a cacophony of sound.

(Marine mammal sounds)

（海洋哺乳動物的聲音）

But when the ice is frozen solid,

而當冰封時，

and there are no big temperature shifts or current changes,

海面下的溫度和洋流無甚變化，

the underwater Arctic has some of the lowest ambient noise levels

北極海面下的環境噪音

是全球所有的海洋當中最低的。

of the world's oceans.

But this is changing.

但是情況正改變著，

This is primarily due to a decrease in seasonal sea ice,

主因是季節性的海冰量減少了，

which is a direct result of human greenhouse gas emissions.

直接肇因於人類的溫室氣體排放。

We are, in effect, with climate change,

實際上，我們和氣候變遷

conducting a completely uncontrolled experiment with our planet.

共同引致這完全失控的星球實驗。

Over the past 30 years,

在過去三十年裡，

areas of the Arctic have seen decreases in seasonal sea ice

北極地區的季節性海冰減少了

from anywhere from six weeks to four months.

六周至四個月之多。

This decrease in sea ice is sometimes referred to as an increase

海冰的減少也是

開放水域季的拉長，

in the open water season.

That is the time of year when the Arctic is navigable to vessels.

北極可行船的時段變長了。

And not only is the extent of ice changing,

不僅冰覆區縮小，

but the age and the width of ice is, too.

冰齡、冰厚和冰寬也變了。

Now, you may well have heard

你可能已聽過

that a decrease in seasonal sea ice is causing a loss of habitat

季節性的海冰減少

使得依賴海冰的動物喪失棲地，

for animals that rely on sea ice,

such as ice seals, or walrus, or polar bears.

例如浮冰海豹、海象或北極熊。

Decreasing sea ice is also causing increased erosion along coastal villages,

海冰的減少也造成 沿海村莊的侵蝕增加，

and changing prey availability for marine birds and mammals.

海鳥和哺乳動物的獵物也變少了。

Climate change and decreases in sea ice

氣候變遷和海冰減少

are also altering the underwater soundscape of the Arctic.

也改變了北極水下音景的風貌。

What do I mean by soundscape?

我所謂的「音景」指的是什麼？

Those of us who eavesdrop on the oceans for a living

我們這些靠聆聽海洋為生的人

use instruments called hydrophones,

用水中聽音器──

which are underwater microphones,

一種水底麥克風 ──

and we record ambient noise --

來聆聽記錄環境噪音。

the noise all around us.

And the soundscape describes the different contributors

而音景描述

音域裡的各個出聲者。

to this noise field.

What we are hearing on our hydrophones

我們透過水中聽音器聽到的聲音

are the very real sounds of climate change.

真實反映了氣候的變遷。

We are hearing these changes from three fronts:

我們聽到的變化來自三方：

from the air,

空中、

from the water

水中

and from land.

和地上。

First: air.

第一：空氣。

Wind on water creates waves.

風吹過水面上產生波浪，

These waves make bubbles;

波浪造成氣泡；

the bubbles break,

氣泡會破裂，

and when they do,

當氣泡破裂時

they make noise.

會發出聲音。

And this noise is like a hiss or a static in the background.

而這聲音就像背景的嘶嘶聲。

In the Arctic, when it's ice-covered,

在冰封的北極，

most of the noise from wind doesn't make it into the water column,

大部分的風聲傳不到水下，

because the ice acts as a buffer between the atmosphere and the water.

因為冰是大氣和水之間的緩衝。

This is one of the reasons

這是北極海面下

that the Arctic can have very low ambient noise levels.

低噪音的原因之一。

But with decreases in seasonal sea ice,

但隨著季節性海冰的減少，

not only is the Arctic now open to this wave noise,

不僅北極的海面下 聽得到波浪的噪音，

but the number of storms and the intensity of storms in the Arctic

而且北極的風暴次數和強度

has been increasing.

也不斷增加。

All of this is raising noise levels in a previously quiet ocean.

這些都使原先安靜的海洋變得吵雜。

Second: water.

第二：水。

With less seasonal sea ice,

隨著季節性海冰的減少，

subarctic species are moving north,

亞北極的物種向北移，

and taking advantage of the new habitat that is created by more open water.

利用擴大開放水域所造成的新棲地。

Now, Arctic whales, like this bowhead,

住在北極的鯨魚例如頭鯨

they have no dorsal fin,

並沒有背鰭，

because they have evolved to live and swim in ice-covered waters,

因牠們已進化適應了 在冰覆的水域裡游泳及生活，

and having something sticking off of your back is not very conducive

假如背上突出個東西，

to migrating through ice,

會不利於在冰間移動，

and may, in fact, be excluding animals from the ice.

且實際上可能根本無法在冰區生活。

But now, everywhere we've listened,

但我們現今在各地聽到

we're hearing the sounds of fin whales and humpback whales

長鬚鯨、座頭鯨和虎鯨的聲音，

and killer whales,

further and further north,

出現在越來越北的地方

and later and later in the season.

和越來越晚的季節裡，

We are hearing, in essence,

本質上說，

an invasion of the Arctic by subarctic species.

我們聽到亞北極物種侵入了北極。

And we don't know what this means.

我們不知道這代表的意涵。

Will there be competition for food between Arctic and subarctic animals?

亞北極物種和北極物種 會爭奪食物嗎？

Might these subarctic species introduce diseases or parasites into the Arctic?

亞北極物種會把疾病和寄生蟲 帶入北極嗎？

And what are the new sounds that they are producing

牠們帶來的新聲音

doing to the soundscape underwater?

會對水下的音景產生什麼影響呢？

And third: land.

第三：土地。

And by land ...

我說的土地

I mean people.

指的是人。

More open water means increased human use of the Arctic.

更大的開放水域意味著 更多人類利用北極。

Just this past summer,

就在剛過去的夏天，

a massive cruise ship made its way through the Northwest Passage --

一艘巨型郵輪通過西北航道──

the once-mythical route between Europe and the Pacific.

這航道曾是 歐洲和太平洋之間的神話路線。

Decreases in sea ice have allowed humans to occupy the Arctic more often.

海冰的減少使得 人類更頻繁地佔用北極，

It has allowed increases in oil and gas exploration and extraction,

增加石油和天然氣的勘探和開採，

the potential for commercial shipping,

使商業航運可通行，

as well as increased tourism.

並增加了旅遊活動。

And we now know that ship noise increases levels of stress hormones in whales

如今我們知道船的噪音 會提高鯨魚體中的壓力激素量，

and can disrupt feeding behavior.

並可能擾亂牠們進食的行為。

Air guns, which produce loud, low-frequency "whoomps"

每十到二十秒產生 大聲而低頻轟聲的氣槍，

every 10 to 20 seconds,

changed the swimming and vocal behavior of whales.

改變了鯨魚游泳和出聲的行為。

And all of these sound sources are decreasing the acoustic space

這些聲源全都減少了

北極海洋哺乳動物 可用來溝通的音域頻寬。

over which Arctic marine mammals can communicate.

Now, Arctic marine mammals are used to very high levels of noise

北極海洋哺乳動物

在一年中的某段時間

習慣於非常高的噪音，

at certain times of the year.

But this is primarily from other animals or from sea ice,

所習以為常的主要是 其他動物或海冰的聲音，

and these are the sounds with which they've evolved,

這些過去與牠們一起演化的聲音

and these are sounds that are vital to their very survival.

對牠們的生存至關重要。

These new sounds are loud and they're alien.

而新加入既吵又陌生的聲音，

They might impact the environment in ways that we think we understand,

可能會以我們已知或未知的方式，

影響環境及牠們的生存。

but also in ways that we don't.

Remember, sound is the most important sense for these animals.

請記住，聲音是這些動物 最重要的感知方式。

And not only is the physical habitat of the Arctic changing rapidly,

不僅北極棲地的形貌正迅速改變，

but the acoustic habitat is, too.

棲地的聲音也變了。

It's as if we've plucked these animals up from the quiet countryside

就好像我們從安靜的鄉村 玃取這些動物，

and dropped them into a big city in the middle of rush hour.

然後把牠們放入 交通尖峰時刻的大城市裡，

And they can't escape it.

牠們落得無處可逃。

So what can we do now?

那麼現在我們該怎麼做呢？

We can't decrease wind speeds

我們無法減慢風速，

or keep subarctic animals from migrating north,

也無法防止亞北極動物往北移，

but we can work on local solutions

但我們可以採用局部解決方案

to reducing human-caused underwater noise.

來減少人為製造水下噪音。

One of these solutions is to slow down ships

解決方案之一

是降低穿越北極的船速，

that traverse the Arctic,

because a slower ship is a quieter ship.

因為慢速的船比較安靜。

We can restrict access in seasons and regions

我們可以在重要的交配、哺育 或遷徙季節和地區

that are important for mating or feeding or migrating.

限制人類的進出。

We can get smarter about quieting ships

我們可以更明智，用較安靜的船隻，

and find better ways to explore the ocean bottom.

以更好的方法去探索海底。

And the good news is,

好消息是

there are people working on this right now.

有人正在執行這些解決方案。

But ultimately,

但最終，

we humans have to do the hard work

我們人類必須努力反轉，

of reversing or at the very least decelerating

或者至少減緩

human-caused atmospheric changes.

人為造成的氣候變遷。

So, let's return to this idea of a silent world underwater.

讓我們回到 寂靜的水下世界這個想法。

It's entirely possible

極有可能

that many of the whales swimming in the Arctic today,

許多今天在北極游泳的鯨魚，

especially long-lived species like the bowhead whale

尤其是像弓頭鯨那樣長壽的物種──

that the Inuits say can live two human lives --

因紐特人說牠們的壽命 是人類的雙倍，

it's possible that these whales were alive in 1956,

極有可能，在 1956 年 雅克·庫斯托拍攝紀錄片的時候

when Jacques Cousteau made his film.

這些鯨魚已經活著了。

And in retrospect,

回想起來，

considering all the noise we are creating in the oceans today,

再看看現今所有 我們在海洋中製造的噪音，

perhaps it really was "The Silent World."

也許當時真的是個「沉默的世界」。

Thank you.

謝謝。

(Applause)

（掌聲）