until the summer ends and they're forced to head south for the winter. 直到夏天结束 它们才会被迫南迁过冬
For the foxes, boom time has come to an end. 对于狐狸来说 美好时光已经接近尾声
Biting flies and the quest for new pasture drives the migration ever onwards. 会叮咬它们的苍蝇以及为了寻找新草场, 驱使它们不停的向前迁徙
They've been searching for days without a sign. 这些狼虽觅食多日 但一无所获
Somewhere in this immense landscape there is food for them. 在这无边无际的大地上的某处 有它们所需要的食物
For them, finding food on the plains is an even greater challenge. 对于狼来说 在茫茫大草原上寻食甚至更为艰辛
So she stashes much of her plunder for later in the year 所以狐狸会把蛋藏起来
She's been waiting for the geese all winter. 它已经等了整整一个冬天
Nonetheless, this female must incubate her eggs for three weeks 然而 雌雪雁必须花三周的时间孵蛋
It's a long way to travel, but for a short period, the tundra is the ideal place for a grazer. 北极的苔原虽然路途遥远, 但仍有短短的一段时间是食草动物的天堂