The mud is a feeding ground for large numbers of birds.

泥地是大量鸟类找寻食物的地区。

They followed their sheep as the were moved from one feeding ground to the next.

他们随着羊群从一个草地迁移到另一个草地。

Mixed flocks of several species often travel together, but when they are feeding or resting you will spot different birds on the ground, at mid-level heights and at the tree tops.

很多种鸟常常混群共同迁徙，但是当他们停下来觅食休息的时候，你就会发现不同的种类有的在地面上，有的在中层高度，有的则在树顶处。

Feeding in trees this way also keeps them safe from ground-based predators, such as foxes.

在树上栖息的方式可以保护它们免受狐狸之类的地面捕食者的伤害。

Meanwhile, the brain also sends messages back to the retina via the centrifugal pathway, which originates from the isthmo-optic nucleus in ground-feeding birds such as pigeons.

同时，脑也通过离中通路对视网膜进行反馈调控，特别是在像家鸽这些地面觅食鸟类中，峡视核就是这条离中通路的起点。