What does Bai Juyi's poem Egret mean?

I'm not completely old until I'm forty, but I have a lot of white hair because of sadness. But why are there some white pendants on the head of the egret by the river without sadness?

The original "Egret":

I'm still in my forties, and my hair is drooping in a hurry. ?

Why are there two egrets by the water, carefree and with silk hanging on their heads?

This poem shows that the beauty of egrets is diverse. First, the static description of the egret's shape, then the dynamic beauty of the egret, his standing posture and the way he flies: on the ridge, on the treetops, in the sky, from low to high in spatial order. The article not only describes the external beauty of the egret, but also describes its internal beauty, praising it as a prose poem in the bones.

Author? Bai Juyi, a native of Weinan, Shaanxi Province, whose real name is Lotte, Xiangshan layman and Mr. Zuiyin. In his early years, he was enthusiastic about helping the world, emphasizing the political function of poetry and doing his best to make it popular. He wrote 60 poems, New Yuefu, Qin Zhongyin, which truly made people sick by singing only, and every sentence must be tuned, just like Du Fu's "Three Officials" and "Three Farewells".

reference data

Ancient Poetry Network: http://so.gushiwen.org/view_22007.aspx