I kind of think that's okay for a scientific observation on it's own, but I guess if I'm going by the pattern of the other answers I gave you, I'd make it more specific.
You can say anything to make it more specific (generally in science though, it's focused on what the experiment is about). So ideas that i think would work: something about the frequency of the chirp, how many times the bird chirped, the volume, the duration of the sound.