猎捕（2015）

在空中 海洋看起来平静无常
From the air, the ocean may appear featureless,
在水面之下
but beneath the surface,
强有力的洋流网络在不停运动
a network of powerful currents is constantly on the move.
正是这些洋流 而不是其它力量
It's these currents, more than any other force,
决定了这里的生物分布
that determine the distribution of life out here.
一整群海洋漂移者
A whole community of ocean drifters
借助洋流搭便车
hitches rides on these rivers in the sea.
远洋红蟹
Pelagic red crabs.
它们聚在一起 以微小的浮游植物和动物为食
They've gathered to feed on tiny floating plants and animals,
洋流滋养了密集的浮游生物
a bloom of plankton fuelled by the currents.
它们腿部的细毛减缓了下降
Fine hairs on their legs slow their descent
然后 尾部摆动几下
and then, with a few flicks of the tail,
它们游回来继续觅食
they swim back up to continue feeding.
洋流不仅携带这些漂流蟹
The currents that carry these wandering crabs
也成为海洋中更大型掠食者的高速通道
also serve as highways for the ocean's larger predators.
条纹马林鱼
Striped marlin.
具有完美的流线体型
Beautifully streamlined,
耗费极小的体力 就能旅行很远的距离
they can travel huge distances with minimum effort.
这些捕猎者在洋流的边界处巡游
These hunters patrol the boundaries between ocean currents,
它们的猎物时常在此聚集
where their prey often gathers.
每只掠食者都具有惊人的嗅觉
Each predator has an incredible sense of smell,
能够探测到猎物留下的微弱痕迹
able to detect faint trails left by their prey.
大猎物就在这里某处
Somewhere out here is the big prize
所有种类的捕猎者正在寻找它
and hunters of all kinds are looking for it.
一大群鱼被密集的浮游生物所吸引
Great shoals of fish are attracted to a plankton bloom.
一群沙丁鱼绵延数英里长
A single school of sardines can be many miles long.
鱼群紧紧聚在一起 数量多更安全
The fish swim tightly together, there's safety in numbers.
它们的防御依靠彼此的配合
Their defence relies on coordination.
遭到攻击时 鱼群整体移♥动♥
When attacked, the sardines move as one.
每条沙丁鱼 会立刻与近邻动作一致
Each fish instantly matches the movements of its neighbour
然后整群鱼同步移♥动♥
and the whole shoal moves in synchrony.
仅仅一只海狮 无法跟上沙丁鱼快速的反应
A lone sea lion can't keep up with their rapid reactions.
即使更多的海狮来了
Even when more sea lions arrive,
看起来也无法攻破沙丁鱼紧密无间的防御
they can't seem to break down the sardines' coordinated defences.
面对这么大的一群鱼 海狮需要分隔出
With a shoal this big, the sea lions need to isolate
更小更容易对付的一群鱼
a smaller, more manageable group of fish.
但掠食者数量太少 鱼群仍然占据优势
But with so few predators, the fish still have the advantage.
海狮能做的就是 将沙丁鱼群困在水面
All the sea lions can do is keep the sardines at the surface
然后等别人帮忙
and wait for others to join them.
金枪鱼
Tuna.
形式开始逆转
Their arrival changes everything.
金枪鱼从下方进攻
Tuna attack from below,
切断沙丁鱼逃回深水区的退路
cutting off the sardines' escape route down to deeper water.
接下来出现的是水剃鸟
Next to appear, shearwaters
不仅善于飞行 在水下也惊人的敏捷
excellent fliers, but also surprisingly agile underwater.
如此多的掠食者从各方向进攻
With so many predators attacking from all sides,
沙丁鱼数量的优势逐渐消失
the advantage starts to shift away from the sardines.
随着鱼群聚得更紧密
As the fish pack ever tighter,
它们的鱼群策略 对掠食者更加容易
their shoaling strategy now makes it easier for the hunters.
短尾真鲨
Copper sharks.
它们嗅到了水中的血腥味
They've scented blood in the water.
令人吃惊的是 掠食者从不彼此攻击
Surprisingly, perhaps, the predators never attack one another.
它们一起合作 将鱼群围成球形
They work together to corral the ball of fish,
轮流一口口地吞食
taking turns to grab a mouthful.
普通海豚
Common dolphins.
随着鱼群变得更小
As the shoal gets ever smaller,
每条沙丁鱼都拼命藏到中间
each sardine scrambles desperately to hide in the middle.
而现在 无处可逃
But now, there's no escape.
一条布氏鲸收拾了残局
A Bryde's whale finishes off the feast
不到一小时 数吨♥沙丁鱼被吞噬干净
tonnes of sardines devoured in less than an hour.
掠食者们消失在蔚蓝之中
The predators melt away into the blue
继续彼此的独行生活
going their separate ways once more.
这条蓝鲸仍在寻找食物
This blue whale is still searching for a meal
以满足巨大的胃口
to satisfy its giant hunger.
体型如此庞大
Being so large,
它必须平均每天捕获4吨♥食物
it must catch an average of four tonnes of food a day.
但可能接连数天不进食
But many days may pass without feeding at all.
正是蓝鲸巨大的体型 使它能够游动最远的距离
It is their great size that enables blue whales to travel the furthest,
漫游热带到两极的每一片海洋
roaming every ocean from the tropics to the poles.
一群浓密的磷虾
Trapped against the surface by fish,
被鱼困在水面
a dense patch of krill.
这条蓝鲸终于找到了
This blue has finally found
期盼已久的猎物
what it's been searching for for so long.
这是一顿值得为之张开巨口的大餐
A meal big enough to make opening its massive mouth worthwhile.
磷虾群蔓延数百米
The krill swarm is hundreds of metres across
十分紧密
and packed tight.
蓝鲸朝着猎物做好准备
The whale lines up on its prey,
瞄准磷虾群最致密的部分
targeting the densest part of the shoal.
带着充满扩张的咽喉 游泳十分费力
It takes so much effort to swim with a fully extended throat
蓝鲸在无形之中停滞下来
that the whale virtually comes to a standstill.
蓝鲸使用舌头将水排出嘴外
The whale uses its tongue to force the water out of its mouth,
使用排列在颚部的鲸须板 将磷虾困住
trapping the krill on plates of hairy bristles that line its jaw.
但过滤这么多水 十分费时
But it takes time to sieve so much water.
这给了更灵活的捕猎者以机会
And that gives more nimble hunters their chance.
蓝鲸可能不如其它捕猎者那么敏捷
Blue whales may not be as agile as other hunters,
但它们不必如此
but they don't need to be.
巨口一张
In one giant mouthful,
它们就能吞下整群磷虾
they can swallow whole swarms of krill.
没有别的捕猎者更适于
No other predator is better suited
利用开阔海洋提供的分散资源
to exploit the scattered riches that the open ocean can provide.
蓝鲸
The blue whale
全世界海洋中最大的捕猎者
the greatest hunter in all the world's oceans.