[00:04:01]These bison are even bigger than their southern cousins

这些野牛较其低纬同类体型更大

[00:07:12]and the largest land animals in North America.

是北美洲最大的陆生动物

[00:10:08]For generations, wolves and bison here

狼与野牛在此代代抗衡

[00:13:29]have been shaped by their battles with each other,

于是得以进化

[00:16:51]making each the most impressive of its kind.

成为同物种的佼佼者

[00:22:16]The bison will not stay long among the trees.

野牛不会在林中栖息过久

[00:25:34]They're not safe here.

这里并非安全地带

[00:28:30]The wolves are closing in,

狼群逐渐靠近

[00:35:37]but their chance of ambushing the bison in the woods has passed.

可惜在林中伏击野牛的机会业已丧失

[00:39:18]Their prey are now in the open

猎物已进入空旷区域

[00:41:14]and grouped together for safety.

结伴而行 以保安全

[00:43:13]The wolves will need to work as a team

狼群若想一击成功

[00:49:41]if they are to make a kill.

便需要协作作战

[00:54:24]They circle the herd, trying to unsettle it

它们呈围攻之势 企图扰乱阵脚

[00:56:55]and split it up.

进而各个击破

[00:58:29]But the bison are armed and dangerous.

不过野牛角锋锐利 相当危险

[01:00:49]They will be safe as long as they stick together.

如能互为犄角 便可保持不败

[01:03:17]The wolves up their game, harrying the herd,

狼群让战斗升级 率先挑衅

[01:12:24]a ploy to trigger a stampede

先对牛群进行骚扰

[01:14:15]and split away one of the smaller ones.

从而孤立出一个孱弱者

[01:19:22]The bison form a defensive circle around their young,

野牛们以幼崽为中心 组成防御性外围

[01:22:06]horns pointing outwards.

它们的角朝外