I’ve had an interest in composing for songbirds, specifically crows (technically songbirds, although their songs are not very popular).
Digression: Linguists Noam Chomsky and Steven Pinker have stated that they see music as an accidental and frivolous byproduct of language evolution, “cotton candy for the mind.” Music is found in all cultures and it is a linear form of communication that is processed by the same parts of the brain as language. But I’ve always thought that this is backwards, that music came first and language piggybacked on top of this.
The difference between bird song and human music is syntax. Bird song can change over time and from place to place, but it’s not like music where the possibilities for ordering and combining elements is endless. It’s like the difference between animal cries (or human interjections like “hey!” and “ow” and tsk-tsk) and language. For reasons I never totally grokked, language is not believed to have evolved from animal cries, so for a bird to produce or appreciate music would not likely be an extension of birdsong.
So, crows… At least some species of crows are thought to be as intelligent as the (non-human) great apes. (Aside: I like that “great apes” is a synonym for Hominidae, which includes the genus Homo.) They are so successful at providing for themselves that they tend to have lots of free time to socialize, play, and make mischief. They’re also quite curious and can produce a wide range of sounds. It seems to me that of any animal, they might be the most ready to develop a taste for music. (Maybe various parrots and other corvids, too.)
Who knows what kind of music might interest crows, though. I’ve played the cracklebox for crows, but they did not find it very compelling.