biomorphosis:

Potoo is a bizarre, nocturnal birds that are rarely seen during the day. They are master of disguise and can easily mistaken for a tree branch. They are monogamous and lay a single egg but place it in the nook of a branch or broken off stem instead of building an actual nest.

Their vocalization has frightened many locals, given rise to folktales throughout its range. According to legend, the call of the Potoo is the mournful lament of a spirit in love with but separated from the spirit of the moon.