so your mom is a heinous bitch. you live under her roof. as i see it, ultimately you're going to have to come up with a compromise solution.
is she always a heinous bitch? maybe it's better to neogotiate later.
i think it's sort of silly to judge an animal for being an animal, as well. so the bird's neurotic. if this was an issue then why didn't we address it when the bird was new in the house? it's not really fair to get up one morning and go "hey, bird's gotta go!" when the bird's being the same as it was every other day.