He hasn't eaten in days.

他已經好幾天沒吃東西了。

This may be his last chance.

這可能是他最後的機會。

(theme music plays).

主題音樂播放）。

I'm two miles above sea level here,

我這裡離海平面兩英里高。

and it is brutal.

而這是殘酷的。

Cold, desolate, hard to breathe.

寒冷，荒涼，難以呼吸。

But, for some, this is home.

但是，對於一些人來說，這裡就是家。

Mountains are one of the most hostile environments

山區是最惡劣的環境之一。

on our planet.

在我們的星球上。

Now, with the rise in global temperatures,

現在，隨著全球氣溫的升高。

life is even tougher.

生活更加艱難。

The relentless search for food.

孜孜不倦地尋找食物。

Intense competition.

激烈的競爭。

Unpredictable weather.

不可預知的天氣。

Mountain animals are pushed to the edge of existence.

山地動物被推到了生存的邊緣。

The Arctic Circle.

北極圈。

Nowhere is the planet warming faster.

沒有任何地方能讓地球變暖得更快。

Spring has arrived here early.

這裡的春天已經提前到來。

And that's bad news for the barnacle geese

而這對藤壺鵝來說是個壞消息。

that breed in these mountains.

在這些山裡繁殖的。

Many nests have failed...

很多窩點都失敗了...

but not this one.

但不是這個。

Three chicks.

三隻小雞。

They're lucky to have made it.

他們很幸運地做到了。

Forced by the early spring,

被初春逼迫。

the parents rush to their migration.

父母匆匆忙忙的遷徙。

They arrived exhausted.

他們到達時已經筋疲力盡。

The female sat on the eggs for 25 days.

雌性在卵上坐了25天。

She's lost 30% of her body weight.

她的體重下降了30%。

But for this family,

但對於這個家庭來說。

the greatest challenge is still to come.

最大的挑戰還在後面。

The parents chose to nest on this 400 foot pinnacle.

父母選擇在這座400英尺的山峰上築巢。

It's the only way to evade predators.

只有這樣才能躲避捕食者。

Just one problem...

只有一個問題...

the grass they eat is a mile away,

他們吃的草是一英里遠。

by the river.

在河邊。

And barnacle geese can't feed their young in the nest.

而藤壺鵝不能在巢中餵養幼鵝。

If the chicks don't feed within 36 hours,

如果小雞在36小時內不進食。

they'll starve.

他們會餓死的。

And these chicks won't be able to fly for another month.

而且這些小雞還要一個月才能飛起來。

The parents are living proof there is a solution.

父母就是活生生的證明，有辦法解決。

Just not an easy one.

只是不容易。

Dad leads the way.

爸爸帶路。

But the chicks are instinctively bonded to mum.

但小雞對媽媽的感情是本能的。

Where she goes they follow.

她走到哪裡，他們就跟到哪裡。

(peeping).

(偷看)。

Incredibly, it survived.

不可思議的是，它竟然活了下來。

But it's stunned.

但它是驚呆了。

And now dangerously exposed.

現在卻危險地暴露了。

(honking, cawing).

(honking，cawing)。

One chick gone.

一個小雞走了。

Now hope rests with the other two.

現在希望寄託在另外兩個人身上。

The back of the spire is a shorter drop.

尖頂的後面是一個較短的落差。

But it's much harder to avoid the rocks.

但要避開石頭就難多了。

For this chick, there will be no escape.

對於這隻小雞，將無法逃脫。

The third and last surviving chick.

第三隻也是最後一隻倖存的小雞。

♪ ♪

♪ ♪

The snow cushions the impact, but offers no grip.

雪可以緩衝衝擊力，但不提供抓地力。

(honking).

(按喇叭)。

Only around 50% of chicks hatched on these cliffs

在這些懸崖上孵化出的雛鳥只有50%左右。

make it through the first month.

熬過第一個月。

With the seasons increasingly unpredictable,

隨著季節越來越不可預知。

fewer chicks will survive.

更少的小雞將生存。

But this chick, at least, has defied the odds.

但這個小妞，至少已經不顧一切了。

A changing climate is affecting life in mountains

氣候變化正在影響山區的生活

across the world.

世界各地的。

Late winter.

冬末。

The average temperature here is rising a degree every decade.

這裡的平均氣溫每十年上升一度。

Bad news for a snow leopard.

對雪豹來說是個壞消息。

Thick fur enables him to withstand temperatures

厚厚的毛皮使它能夠承受溫度

of -20 Fahrenheit.

零下20華氏度。

But today, it's 66.

但今天，它是66。

To find enough food, he must patrol a territory

為了找到足夠的食物，他必須在一個區域內巡邏

of 80 square miles.

的80平方英里。

Dry barren slopes don't support much prey.

乾燥的荒坡並不能養活多少獵物。

It can be more than a week between meals.

兩餐之間的時間可能超過一週。

He must make a kill,

他一定要殺個痛快。

or starve.

或者餓死。

BEAR: 16,000 feet up in the Himalayas,

熊：在喜馬拉雅山的16000英尺高處。

a desperately hungry snow leopard.

一隻極度飢餓的雪豹。

His best opportunity in days is within sight.

他這幾天最好的機會就在眼前。

Blue sheep.

藍羊。

In this heat, he can't run far.

在這種熱度下，他是跑不遠的。

He needs to close the gap.

他需要縮小差距。

His camouflage helps.

他的偽裝有助於。

But with so little cover, it's hard to get close enough.

但是，遮擋物太少，很難靠近。

He ran too early.

他跑得太早了。

And it's too hot to give chase.

而且天氣太熱，不能追。

Like all who live here,

像所有住在這裡的人一樣。

his fortunes are linked to the mountain climate.

他的命運與山區氣候有關。

And even small changes can have dramatic consequences.

而即使是微小的變化，也會產生戲劇性的後果。

Here in Africa, rising temperatures

在非洲，氣溫上升

are forcing mountain life ever higher.

正在逼迫山區生活越來越高。

An army of Gelada monkeys is gathering.

一支仡佬族猴子大軍正在集結。

They're all after one thing.

他們都在追求一件事。

But to find it, they must climb higher and higher.

但要找到它，他們必須爬得更高更遠。

Their numbers grow to 1200 strong.

他們的人數增長到1200人。

One of the largest gatherings of monkeys on the planet.

地球上最大的猴群聚集地之一。

At 10,000 feet, this is what they're after.

在一萬英尺的高度，這就是他們的目標。

Grass.

草。

It's almost all they eat.

這幾乎是他們的全部食物。

But so many monkeys in such a small area means trouble.

但在這麼小的範圍內，這麼多猴子就意味著麻煩。

Especially for this old male.

尤其是對於這個老公子來說。

He needs a lot of energy to defend his family.

他需要大量的精力來保護自己的家庭。

Ten females and 12 youngsters.

10名女性和12名年輕人。

But you don't get much from grass.

但你從草上得不到什麼。

He has to spend ten hours a day feeding.

他每天要花十個小時餵食。

And today he's gonna need all the energy he can get.

今天，他需要所有的能量，他可以得到。

Bachelor males.

單身男性。

Outcasts.

被遺棄者。

Forced to the edge of society.

被迫到社會的邊緣。

Any one of them would be happy to take down the old male and

他們中的任何一個人都會很樂意把老公公和

become the new family leader.

成為新的家族領袖。

To hold onto power, the old male must prove his strength,

老公要想掌握權力，必須證明自己的實力。

both to the bachelors and his females.

無論是對單身漢還是他的女性。

He challenges them to chase him.

他挑戰他們去追他。

(barking, yelling).

(吠叫，大叫)。

But no one dares to attack.

但沒有人敢攻擊。

His show of force has worked.

他的武力展示已經奏效。

For now.

目前來說

The old male has little time to refuel

老公子沒時間加油

before the herd moves on.

趁著牛群還沒走，

The bachelors are back.

單身漢們回來了。

(barking, yelling).

(吠叫，大叫)。

At this high altitude,

在這種高海拔地區。

each confrontation takes more energy.

每一次對抗都需要更多的精力。

A relentless cycle of moving, feeding and fighting.

遷徙、進食、戰鬥的無情循環。

Moving, feeding, fighting.

搬家、餵食、打架。

By late afternoon, the old male is exhausted.

傍晚時分，老公已經筋疲力盡。

The strongest bachelor, 45 pounds of muscle,

最強的單身漢，45斤的肌肉。

with energy to burn.

與能量燃燒。

He's the most serious challenger yet,

他是目前最認真的挑戰者。

and the old male knows it.

而老公也知道。

BEAR: Two male Gelada monkeys fight for supremacy.

熊：兩隻雄性蓋拉達猴爭奪霸主地位。

A dominant male and a younger bachelor.

一個是霸道的男性，一個是年輕的單身漢。

One against one the bachelor is stronger.

一對一的單身漢更強。

The old male won't last much longer.

老公的壽命不會太長。

At least not alone.

至少不是一個人。

His females are loyal.

他的雌性是忠誠的。

They won't give up on their protector yet.

他們還不會放棄自己的保護者。

This united force is overwhelming.

這種團結的力量是壓倒性的。

The old male is victorious.

老公勝利了。

But it's tough at the top.

但在上面很辛苦。

As the climate warms and the grass they depend on retreats higher,

隨著氣候變暖，它們賴以生存的草叢也越退越高。

their battle for survival will only intensify.

他們的生存之戰只會愈演愈烈。

In the heat of mid-summer, mountain goats seek out

在炎熱的仲夏，山羊在尋找

cooler temperatures on the high ridges.

高山脊上溫度較低。

This female is a natural mountaineer.

此女是天生的登山家。

She can easily access the best grazing,

她可以輕鬆地獲得最好的牧草。

even with a kid in tow.

即使帶著孩子

But there's one thing they both need that's

但有一樣東西是他們都需要的，那就是

far harder to reach.

遠遠難以達到。

Today, they must leave the ridge and descend

今天，他們必須離開山脊，下山。

into the heat of the valley.

入谷的熱度。

For the little one, this is a dangerous journey.

對於小傢伙來說，這是一次危險的旅程。

With the mercury hitting 100 degrees Fahrenheit,

隨著水銀溫度達到華氏100度。

this is the hottest summer on record.

這是歷史上最熱的夏天。

After a winter of heavy snow,

經過一個冬天的大雪。

this means more meltwater than ever.

這意味著比以往更多的融水。

Mum's made this journey before,

媽媽以前也走過這段路。

but some rivers are at their highest level in 100 years.

但有些河流卻達到了百年來的最高水準。

♪ ♪

♪ ♪

Their goal is in sight.

他們的目標就在眼前。

Just one more river to cross.

只是還有一條河要過。

But it's the deepest and widest yet.

但這是最深最寬的一次。

The current is too strong for little legs.

水流太大，小腳不方便。

And this is what they've risked their lives for.

這就是他們冒著生命危險的原因。

A salt lick.

舔鹽。

These goats crave sodium, an essential mineral lacking

這些山羊渴求鈉，而鈉是缺乏的基本礦物質。

in their mountain diet.

在他們的山區飲食中。

Summer in the mountains is short.

山裡的夏天很短。

Harder times are coming.

更加艱難的時刻即將到來。

Temperatures plummet.

氣溫驟降。

Days shorten.

日子縮短了。

Winter is here.

冬天到了。

But the hunt for food must continue.

但尋找食物的工作必須繼續。

Heavy snow on higher ridges has forced these ibex

高處山脊上的大雪迫使這些山羊不得不離開

down into the valley.

下到山谷裡。

A cold winter can be a blessing for

寒冷的冬天可以是一種福氣，對於

a hungry snow leopard.

一隻飢餓的雪豹。

He's less likely to overheat.

他不太可能過熱。

But against the white, he's visible for miles.

但在白色的襯托下，他在幾英里外都能看到。

He must rely on stealth.

他必須依靠隱身術。

Not easy in such deep snow.

在這麼深的雪地裡，不容易。

♪ ♪

♪ ♪

The distance was too great.

距離太遠了。

The ibex too fast.

ibex的速度太快了。

Now all the animals in the valley know he's here.

現在山谷裡所有的動物都知道他在這裡了。

And he's burnt precious energy.

而且他已經消耗了寶貴的能量。

These are desperate times.

這是一個絕望的時代。

If he's to see winter through,

如果他要熬過冬天。

he may have to take bigger risks.

他可能要承擔更大的風險。

Throughout the mountains of the Northern Hemisphere,

整個北半球的山區。

winter's grip is tightening.

冬天的魔爪越來越緊。

Animals must make the most of any last opportunity before

動物們必須充分利用最後的機會，在

conditions drive them to take shelter.

狀況驅使他們去避難。

Far above, planetary forces are on a collision course.

遙遠的上空，行星的力量正在發生碰撞。

A river of air, the jet stream,

一條空氣的河流，噴射流。

flows around the North Pole.

繞著北極流動。

At its center, sits a mass of cold Arctic air.

在它的中心，坐著一團北極的冷空氣。

But now a warming upper atmosphere is slowing the jet stream.

但現在高層大氣變暖，減緩了噴氣流的速度。

And the cold air can escape.

而冷空氣卻可以逃逸。

By the time it hits The Rockies,

到了落基山脈的時候。

it's grown into a mega storm.

它已經成長為一個巨大的風暴。

Freezing everything in its path.

凍結一切在它的路徑。

BEAR: In the depths of winter, extreme storms rage across

深冬時節，極端的暴風雨肆虐著整個城市。

Canada and the USA.

加拿大和美國。

Freezing temperatures,

凍結溫度。

wind speeds of up to 150 miles per hour.

風速可達每小時150英里。

Now, even the toughest animals are at their limit of survival.

現在，即使是最強悍的動物也到了生存的極限。

(wind whistling).

(風呼呼)。

The storms may have passed, but there is hidden danger

風暴雖已過去，但隱患猶存。

in this landscape.

在這個景觀中。

Winter storms have buried this area of British Columbia

冬天的暴風雨將不列顛哥倫比亞省的這一地區掩埋了。

under nearly 40 feet of snow.

在近40英尺的積雪下。

But if temperatures rise above freezing,

但如果氣溫上升到冰點以上。

it can have lethal consequences.

它可能產生致命的後果。

On the high ridges, wind driven snow has created

在高高的山脊上，風吹的雪造成了

huge overhangs, some 25 feet thick.

巨大的懸崖，約25英尺厚。

The longer the temperatures stay above freezing,

溫度在冰點以上停留的時間越長。

the more the snow pack weakens.

雪層越是薄弱。

(crashing).

(崩潰)。

Soon, tens of thousands of tons of snow are traveling

很快，數萬噸的積雪就被運走了。

up to 80 miles an hour.

時速可達80英里

As weather patterns change, avalanches across the world

隨著天氣模式的變化，世界各地的雪崩

are growing bigger.

正在變大。

The more erratic and severe mountain winters become,

山區冬季越是反覆無常，越是嚴峻。

the more victims they'll claim.

他們就會要求更多的受害者。

But some are still succeeding in this harsh world.

但有些人還是在這個殘酷的世界裡獲得了成功。

Golden eagles live in almost every mountain range in the

金雕生活在幾乎所有的山脈中。

Northern Hemisphere.

北半球。

They endure the alpine winter by using the brutal conditions

他們利用殘酷的條件忍受著高寒的冬天

to their advantage.

對他們有利。

Like all golden eagles, this female has a special sensory

就像所有的金雕一樣，這隻雌性金雕有一種特殊的感覺。

organ that detects change in air pressure,

檢測氣壓變化的器官。

allowing her to locate air currents rising off ridges.

讓她能夠定位從山脊上升起的氣流。

With her seven foot wingspan, she can climb to over 11,000 feet.

它的翼展有7英尺，可以爬到11000英尺以上。

Then, to get to the next peak, she folds her wings and dives.

然後，為了到達下一個山峰，她折翼俯衝。

With a top speed of 150 miles per hour,

最高時速可達150英里。

she's one of the fastest animals on the planet.

她是地球上最快的動物之一。

It looks effortless, and it needs to be.

它看起來毫不費力，也需要這樣。

A golden eagle may cover 100 miles a day scouring

一隻金雕一天可以飛100英里，到處亂竄

the slopes for any opportunity.

在斜坡上尋找任何機會。

A flock of ravens is a good sign.

一群烏鴉是個好兆頭。

(cawing).

(cawing).

During winter, golden eagles are forced to scavenge

冬天，金雕被迫覓食。

90% of their food.

90%的食物。

If finding food is hard, keeping it is even harder.

如果說找食物難，那麼保住食物就更難了。

A carcass like this attracts a lot of attention.

這樣的屍體會吸引很多人的注意。

This male is powerful.

這個公子很厲害。

And eagles don't share.

而老鷹不分。

Another brutal storm.

又是一場殘酷的風暴。

This could be the last chance to feed for days.

這可能是幾天來最後一次餵養的機會。

Starvation is a serious threat.

飢餓是一個嚴重的威脅。

Only a quarter of young eagles will survive to reach maturity.

只有四分之一的幼鷹能活到成熟。

Will it be him or her?

會是他還是她？

Attacking from the air gives her the advantage.