For the North American musk oxen, this is rutting season.

对牛来说，这正是求偶的季节。

At summer's end, male bison help to move the sun-baked soil as the rutting season starts.

夏末，随着发情期的开始，雄性公牛也开始帮助翻动太阳晒过的土。

But we can be much more specific than this even, because we're clearly looking at these animals in the autumn, at the time of rutting and migration to winter pastures.

我们还可以更进一步地具体描绘，显然我们观察到的，是秋天时向冬季牧地进行大迁移的。

They had grabbed each other by the shoulders and were carrying out a Staring Contest, the horns on their helmets locked together like a couple of rutting stags.

他们抓住彼此的肩膀，正在进行一场凝视比赛，他们头盔上的角紧紧地锁在一起，就像两只公。