我们的星球（2019）

‎莫过于北极
than in the Arctic.
‎今年的气温
This year, the temperature climbs
‎上升到了惊人的38摄氏度…
to a staggering 38 degrees Celsius...
‎导致海冰以前所未有的速度融化
melting sea ice faster than ever.
‎一种北极动物受此影响最大
And one Arctic animal is affected more than most.
‎为了吃食
To feed
‎海象需要浅层海床
walrus need a combination of a shallow seabed
‎丰富的蛤类
abundant clams
‎以及可供休息的浮冰
and ice floes on which to rest.
‎然而 如今这样的地方已越来越少
But there are now fewer places to do so.
‎这使得每年的夏季 ‎都比上一年更加难熬
Making each summer more difficult than the last.
‎对于刚做母亲的海象而言更是如此
Especially so for a new mother.
‎三天前 ‎她不得不离开海象群独自生产
Three days ago, she had to leave the herd to give birth on her own.
‎从那之后 她一直守在小海象身边
And since then, she hasn't left her calf's side.
‎哺育期的海象妈妈 ‎所需的食物几乎是原来的两倍
Nursing mothers need nearly twice as much food.
‎但她们不能离开幼崽自己进食
But they can't leave their calves alone while they themselves feed.
‎所以 她必须找寻其它海象
So she must go in search of others
‎帮她照顾幼崽
to help her care for her young.
‎小海象一生下来就会游泳
A newborn walrus is able to swim from day one.
‎但他还不够强壮 无法远行
But he's not yet strong enough to travel far.
‎所以 第一次旅程
So, for his first journey
‎他搭了便车
he hitches a ride.
‎浮冰数量逐年减少
With fewer ice floes each year
‎海象只能游到更远的地方寻求帮助
they must swim further to find help.
‎而在求助成功之前 ‎海象妈妈都无法进食
And until then, his mother can't feed.
‎即便找到其它海象
Even when they do find others
‎还必须要有足够低矮的浮冰 ‎让小海象能够爬上冰面
the ice must be low enough for the calf to climb out.
‎太高了
Too high.
‎这块看起来刚刚好
This looks just right.
‎然而 适宜的浮冰太过稀少
But with suitable ice in short supply
‎空间十分有限
space is very limited.
‎这并不是它们所需要的欢迎
It's not the welcome they needed.
‎就算有空间足够的浮冰
Even when there's enough ice
‎没有帮手 海象妈妈依旧无法觅食
without anyone to help, she is unable to feed
‎只能守着小海象
and must stay with her calf.
‎它们必须继续寻找
Their search must go on.
‎在接下来的三年里 ‎小海象都要依赖妈妈
The calf will depend on her for the next three years.
‎不管妈妈去哪里
Wherever she goes
‎幼崽都跟着
they will go together.
‎未来十年内 ‎夏季海冰可能会完全消失
In the next decade, the summer sea ice could disappear altogether.
‎一旦发生这种状况
If that happens
‎即便是北极最老练的旅行者
even for the Arctic's most seasoned travelers
‎都可能无处可去
there may be nowhere left to go.
‎六月下旬
In late June
‎北半球感受到地球倾斜的全面影响
the North feels the full impact of the Earth's tilt
‎日照量也到达一年中的顶峰
and receives more daylight than at any other time.
‎在太平洋的某处角落
And, in one corner of the Pacific
‎此时也是一年中的绝佳机会
this creates the greatest opportunity of the year.
‎六个月来
For six months
‎阿♥拉♥斯加的白令海 ‎一直显得毫无生气 苍茫空虚
Alaska's Bering Sea appears lifeless and empty.
‎尔后 在六月的某日…
Then, one day in June...
‎一切都变了
all that changes.
‎一只只座头鲸
Humpback whales arrive
‎经过历时一个月的旅程到达此处…
after a month-long voyage...
‎参加鲸界顶级盛事
for the biggest event in their calendar.
‎数千只座头鲸
Thousands of them.
‎太平洋之上
Across the Pacific
‎其他的旅客也在纷纷赶路
other travelers are also on their way.
‎灰鹱日夜兼程 想要及时赶到…
Sooty shearwaters race to get there in time...
‎单日不间断飞行一千公里
flying 1,000 kilometers a day nonstop.
‎如此重要场合
The occasion is so important
‎它们甚至不辞辛苦 ‎从世界的另一边赶来
they come from the other side of the world.
‎六万五千公里
At 65,000 kilometers
‎这是地球上动物迁徙的最远航程
it's the longest animal migration on Earth.
‎数百万只灰鹱加入鲸群的行列
A million of them join the whales.
‎大家纷纷来此觅食
All have come to feed.
‎这是地球上最为壮观的聚会之一
It's one of the greatest gatherings of life on Earth.
‎就在五个月前
Here, five months ago
‎这里每日光照时间只有七小时
there were just seven hours of light a day.
‎而现在 光照时间长达17个小时
Now, there are 17.
‎这种变化 ‎使得浮游生物和磷虾的数量激增
The change triggers an explosion in the numbers of plankton and krill.
‎对这些鲸鱼而言 ‎这可能是一整年中唯一的饱餐机会
For the whales, it may be the only time they feed in the entire year.
‎整个夏季
Over the summer
‎每头鲸鱼收入腹中的食量可达900吨♥
each scoops up 900 tons of food.
‎它们只有90天时间可以尽情美餐
They all have just 90 days to eat as much as they can.
‎很快 白天缩短
Soon, the days will shorten
‎饕餮盛宴也将结束
and bring an end to the great feast.
‎到时 它们都将返回南方
Then, every one of them will return south.
‎地球的倾斜之旅所带来的种种良机
The opportunities brought by our tilted planet's journey
‎既巨大又短暂
can be enormous yet fleeting.
‎经历了一个月的漫长暑日
After a month of long summer days
‎北太平洋的温度已经达到最高峰
temperatures in the North Pacific are reaching their peak.
‎海洋中一位捕食者察觉到了变化
An ocean predator detects the change
‎并且规划了新的航道
and sets a new course.
‎一只虎鲨
A tiger shark
‎长途跋涉一千公里 横跨太平洋
on a thousand-kilometer odyssey across the Pacific.
‎在地球磁场的引导下
Guided by the Earth's magnetic field
‎她径直向目的地…
she swims in a straight line towards her target...
‎莱桑岛游去
Laysan Island.
‎无独有偶
And she's not the only one.
‎这一物种经历了漫长的旅程 ‎堪称鲨鱼迁徙的距离之最
This species makes some of the longest journeys of all sharks.
‎而且虎鲨猎食的动物 ‎也比其他鲨鱼更加广泛
And hunts a bigger range of animals than any other.
‎其中甚至还包括鸟类
Including even birds.
‎这只莱桑信天翁
The Laysan albatross chick hasn't eaten
‎自两周前被父母抛下后 就再未进食
since he was abandoned by his parents two weeks ago.
‎为了觅食
To find food
‎他必须离开小岛
he must now leave the island.
‎但世界上最大的海鸟 ‎起飞需要借助很大的风力
But the world's largest seabirds need a lot of lift.
‎风随时会来
That could come at any moment.
‎七月 在高温作用下 ‎海上会形成热带风暴…
In July, the high ocean temperatures generate tropical storms at sea...
‎把风带到莱桑岛
bringing wind to Laysan
‎也为信天翁雏鸟送来了离岛的旅票
and the young albatross a ticket out of here.
‎微风渐劲
The breeze continues to build
‎甚至有足够的力量托起一只信天翁
until there's enough to lift even an albatross.
‎黑脚信天翁的雏鸟总是率先起飞
And the black-footed chicks are always first to go.
‎雏鸟的第一次飞行向来不会长久
A chick's first flight is never a long one.
‎而在此处 这通常也是最后一次飞行
And here, it's often their last.
‎虎鲨来了
The tiger sharks have arrived.
‎而且不会轻易失手
And they are very effective.
‎这让年幼的信天翁不免心生畏惧
For the young albatross, it's not exactly encouraging.
‎然而 机不可失
But it's now...
‎时不再来
...or never.
‎如果他到达远洋水域
If he reaches the open ocean
‎很可能五年内都不会着陆
he may not touch land again for five years.
‎然而 没有犯错的余地
But there is no room for error.
‎是时候抛开谨慎顾虑
Time to throw caution to the wind.
‎该起飞了
Time to fly.