"A pair of swallows flies in the sky with their wings, sometimes low and sometimes high."

The first three chapters of the Book of Ballads in Book of Songs describe swallows taking off, flying, and murmuring. The poet contrasted the sorrow and sadness of a friend's parting with the freedom of swallows.

Today, swallows are viewed as being full of vigor and vitality. In Haizhu Wetland, swallows are also heroes for eliminating pests and greening the environment. One swallow can catch 1.2 million flies and mosquitoes in just one summer.

A swallow in Haizhu Wetland. [Photo/WeChat account: gzhzfb]