蓝色星球（2001）

Walruses spend nearly all their lives at sea,
海象几乎一生都在海里
but each year for just a few weeks...
但每年只有几周
...they have to return to the coast.
它们必须回到岸边
They seek out isolated beaches like this one on Round lsland in the...
它们会找像罗德岛这样孤立
...far northern Pacific
并远离北太平洋的海滩
Suitable sites like this, free from bears, are so scarce...
像这样没有熊的合适地点 非常稀少
...that at times as many as fourteen thousand animals
因此有时数量达1万4千的动物
will cram themselves on to this...
会全部挤在
...one beach
这一个岛上
When they first emerge from the sea the walrus are white
海象一开始从海中出现时 颜色是白的
That's because being warm-blooded animals living in very cold ocean,
这是由于生活在 冰冻海水中的温血动物
they conserve heat by...
维持温度的方式
...keeping their blood concentrated in the core of their bodies
是将血液保存在身体的中♥央♥
On land it's warm enough for them to allow their...
陆地上温度够暖和
...outer blood vessels to dilate and that turns their skin from white to pink
所以它们外♥围♥的血管扩张 而使皮肤由白转粉红
Now they can moult the outer layers of their skin,
现在它们可以脱去外皮
rubbing themselves up against the rocks
在岩石上摩擦身体
But more than anything else coming to land
但登上陆地最值得的是
brings the walrus relief from having to spend energy
它们可以不用再耗体力
maintaining their body temperature in an icy-cold ocean
来维持在冰水中的体温
Heat conservation, in fact, may well be the primary reason so many...
温度的保持也许是 每年众多
...sea mammals are forced to return to the land each year
海洋哺乳类 被迫回到陆地的主要原因
The world's coldest seas are in Antarctica
地球上最冷的海在南极
Each spring, half the world's Southern Elephant seals
每个春天半数的南方海象
return to the island of South Georgia
会回到南乔治亚岛
Elephant seals have particularly thick insulation of blubber that keeps them warm
海象有特别肥厚的脂肪 来帮助保暖
For them breeding is the only reason to leave the sea
繁殖是它们 离开海水的唯一理由
With temperatures down to minus 20...
当气温降到零下20度
...and hundred mile an hour winds, it can't be comfortable out on the beach,
风速达每小时100里 海滩上绝不是舒服之处
but heat dissipates more rapidly through water...
但热度在水中消失的速度 比空气中快
...than through air so even in these conditions...
因此即使在这种状况下
...their young which at first don't have a thick coat
没有肥厚脂肪的年轻海象
of blubber will be far warmer on the land
在陆地上会温暖许多
Once the males are established on the beach the females soon follow
一旦雄性在海滩上站稳阵脚 母海象便随之跟进
Within just ten days the empty beach fills up with six thousand elephant seals
十天内空旷的海滩 顿时挤满了6千只海象
Almost immediately the females give birth to pups sired the previous year
母海象即刻产下 前一年所怀之胎儿
Their milk is very rich and the pups grow astonishingly quickly
它们有充足的奶水 而小海象的成长速度更是惊人
ln just three weeks they turn form thin bags of skin to fat balls of blubber
它们在3周内从皮包骨 转而成为一团肉球
As soon as they've given birth,
生产过后
the females become sexually receptive again...
母海象即刻恢复性♥欲♥ 在如此
...and it's now that the advantages of breeding
密集聚落中繁衍的好处
in such dense colonies become clear
此刻得到证实
Females can make their choice from many males,
母海象能从众多异性中选对象
while successful males can have access to lots of females
而厉害的公海象 则可同时有多个配偶
But to gain that access and control a harem of females,
但要掌控成群的母海象
the bull must be prepared to fight
公海象必须准备好迎战
The larger the male, the louder the roar and the more likely he is to win
体积和吼声越大的 越有可能获胜
When males are well matched these bloody battles will last twenty minutes or more
当两方势均力敌，血腥的争斗会持续 约20分钟或是更多
Eventually, the loser retreats into a stream already pink with his own blood
战败者最后会退回 已被自己的血染红的水里
These battles certainly help females select the strongest bulls...
这些争斗有助于母海象 挑选最强壮的伴侣
...but they bring great dangers for the pups.
但却为小海象带来极大的危险
Each year, in the denser parts of the colony,
在聚落较密集的地区
a fifth of the pups are crushed to death
每年有5分之1的小海象被压死
This is why it may be better to mate
因此在海滩边缘处交♥配♥
at the edge of the beach close to the sea
也许是较好的选择
Less dominant males hide in the surf
较懦弱的雄性会躲在浪里
They are waiting to try and steal an illicit mating...
它们等待也企图偷袭
...with females as they come and go
来来往往的母海象
This male knows he has been spotted by the big bull
这只公海象知道自己 已被在此区称王的雄性盯上
who claims all the females on this part of the beach
在大团体中繁衍对幼儿
Breeding in groups can bring advantages to pups as well as to adults
及成年者都有益处
Along the coast of Patagonia southern sea lions breed together each year
巴塔哥尼亚海岸的海狮 每年在数以百计的
in groups several hundred strong
聚落中繁殖
For the growing pups these colonies act rather like a school
对成长中的小海狮而言 这些聚落其实较像是学校
The bonds and relationships developed here on the beach
它们在此学到的团结和关系
may be vital for the rest of their lives
对一生来说有绝对的重要性
Sea lions are very social animals and as adults and young forage together,
海狮是交际频繁的动物 也因为年轻与年长者一同觅食
they probably share...
它们大概会分享
...information about the location of good feeding sites
觅食地点的讯息
Conditions here could hardly be better for the growing youngsters
这儿的状况 对成长中的幼儿来说实非恰当
As the tide goes out it leaves behind a selection of sheltered pools
潮水退去后 留下的是众多隐蔽的水池
Perfect places for learning to swim
也是学习游泳的绝佳地点
At high tide...
涨潮时
...it is easy for the pups to take their first experimental dips in the surf
小海狮轻易地 就能尝试跳入浪中
A killer whale
杀人鲸
These young pups have never seen anything like it before
这些小海狮从未见过 如此庞大的东西
The Whales though are very experienced
然而这些鲸鱼却已司空见惯
Each year this same group turns up along the coast
每年这群鲸鱼准时在
at precisely the same time as the pups are starting to swim
小海狮开始游泳时出现
The whales need to surprise the pups,
鲸鱼必须让小海狮出乎意料
so they have stopped calling to one another and keep silent
所以它们暂停对彼此的呼叫 以保持安静
Speed is everything
速度是致胜关键
The whales do not take pups that are out of the water,
鲸鱼不会攻击 离开水面的小海狮
but sometimes their momentum drives them right up the beach
但有时冲力会将它们带到海滩
and then there's real danger of getting stuck
这时它们便会有搁浅的危险
The whale has to thrash in this frenzied way to get off the beach
这只鲸鱼须靠猛烈的拍击 从海滩上脱困
Most of the pups are taken into deep water while they're still alive
多数的小海狮被带入水中时 仍是活着的
And there the whales - apparently - play with them
在水中 显然鲸鱼们拿它们来把玩
Often an adult whale is joined in the game by a youngster
通常幼鲸会加入 成年鲸鱼的游戏
lt may be learning how to grab a seal pup before it risks a drive up the beach
它可能在学会如何在 游上海滩前//就先学会抓住小海狮
Whatever the reason the seal pup - still alive
仍活着的小海狮无缘无故
is tossed back and forth for over half an hour
被丢来丢去超过半个小时
Even when the pup is dead, the whales' sport is not completely over
即使小海狮已经死了 鲸鱼们的游戏运动仍不结束
We can only speculate at the real reasons behind this extraordinary behaviour
我们能做的只有推测 这种奇特行为背后的原因
But for the whales, the hunting season is a short one
对鲸鱼来说 狩猎的季节很短
Before long the pups learn to stay well clear of the water
小海狮很快的学会远离海水
and the whales become less and less successful
鲸鱼的成功率就渐渐降低了
After just two weeks, they move on
两周后，它们便离开了
The killing season is over
杀戮的季节结束
That's how it often happens along the coast
这就是海岸的生态
Things are always changing
事情不断在变化
They're never the same for long in this,
从来不曾始终如一
the most dynamic of all the ocean's habitats
就在这海洋生态中最多变的地方