The gray wolf once had the largest distribution of any mammal beside humans and they're highly intelligentpredators.
灰狼曾经是除了人类之外分布范围最广泛的哺乳动物，它们也是具有高智商的掠食者。
Most gray wolves stay within the territory where they were born.
大多数灰狼只在它们的出生地附近活动。
But in some parts of the tundra, gray wolves must travel great distances to survive.
但在苔原上的某些地方，灰狼必须远距离活动才能够生存。
This wolf pack is following the reindeer tracks out of the taiga forest onto the icy plains of the tundra. And when they find the herd, the hunt will be on.
这群狼正跟随着驯鹿的足迹走出泰加林地来到冰冷的苔原之上。而当它们发现驯鹿群时，捕猎就会开始。
The gray wolf is one of the deadliest killers on the planet.
灰狼是地球上最致命的掠食者之一。
They'regularly take down bison six times their size. But here on the Arctic tundra, reindeer are their stable food.
它们经常制伏六倍于自己体型的北美野牛，但在这北极苔原上，驯鹿就是它们的主食。
With up to ten wolves close in, the pack tries to split the herd.
多至十头狼迫近驯鹿群，试图将它们分开。
If they can separate them, they can identify the weak.
一旦将驯鹿群分开，它们就可以找出体弱的驯鹿。
The reindeer try desperately to stay together, but the wolves conserve energy, waiting for their moment to strike.
驯鹿们竭力地保持不被冲散，但狼群保存着体力伺机发动攻击。
Each wolf requires an average up to four and half kilograms of meat a day and this pack must make a kill every few days.
每头狼每天平均需要四点五公斤的肉食，所以这群狼必须每隔几天就捕猎一次。
Having finally split the herd, the wolves close in.
终于分开了驯鹿群，狼群开始逐渐迫近。
The hunt is on. The reindeer must stay together.
捕猎开始了，驯鹿们必须聚在一起。
This young female separates from the herd.
而这头年轻的雌鹿却脱离了鹿群。
A reindeer could easily outrun one wolf, but the wolf pack is working together.
一头驯鹿可以轻身地跑羸一头狼，但狼群是协同作战的。
