Old water-bird character

It is a variant spelling of the old bird-name 鶂.

Older glosses describe 鶂 as a water bird that flies high, and the Yupian dictionary lists 𪁌 as another spelling. Shuowen Jiezi, a Chinese character dictionary, calls the related form 鶃 a bird and cites the Spring and Autumn chronicle’s account of birds flying backward past Song; traditional commentary explains the flight as wind. A note attributed to the writer Sima Xiangru links a form to 赤 (“red”); it describes a spelling, not a red-bird meaning.

Why was the bird painted on boat prows?

It served as a protective image on boat prows.

A Ming-era Chinese miscellany—a collection of short notes—says the bird was painted on prows to ward off water spirits. The compound 鷁首 means “bird prow” and can name the boat itself.