Tiels are great birds, I used to handfeed them for my mother who raised birds to sell. If this was someone's pet, and it sounds like it was, it may even talk once it calms down and gets used to things. The sound of a Tiel talking with its high, squeaky voice, is hilarious! Mainly though, they carry a tune quite well and you can teach them to whistle just about anything.
Good Luck!