纪录片《我们的地球》 第352期 广袤草原(17)（在线收听）

Five hundred miles further north than any tree can survive, grass returns to life.

在树木生存极限八百公里以北的地方，青草春风吹又生。

Caribou females have journeyed to the far north to calve.

雌性北美驯鹿远赴北方，来此产仔。

Over 70,000 caribou babies will be born in the next few days.

超过七万只驯鹿幼崽将在几天内出生。

As the calves appear, so too do the leaves of the newly sprouting grass.

小鹿出生的时候，也正是青草发新芽的时候。

And the calves must strengthen quickly.

幼鹿必须迅速增强体能。

Within days they will have to keep up with their parents on a never-ending march.

几天内他们就将跟随自己的父母踏上无尽的征程。

At one day old, they're already faster than an Olympic sprinter.

第一天，他们的速度就已经超过人类短跑健将。

They're testing the legs that will carry them thousands of miles, better to learn their limitations now.

他们正在测试自己跋山涉水用的四肢，最好现在就知道极限在哪里。

It may look playful, but there's no harder life on the grasslands than that facing these infants.

看起来很好玩，但草原上最艰苦的生活正等着这些他们。

The caribou mothers now join together, each with an infant exactly the same age.

母驯鹿现在聚集起来，每只都带着一只同样大小的幼鹿。

They're setting off on the greatest overland trek made by any animal.

她们准备启程，进行陆地上最伟大的长途跋涉。