The biggest point for me is why they scream. I do not have large parrots, but my lovebirds can be really noisy. Most of the time it is obvious they are just having fun, practicing sounds and all that, sometimes they call for me(I respond but we live in the same room so I rarely hear this anymore, they might call when I am outside already but by then I cannot hear them), and sometimes they are really upset about something. In that case I try to calm them of course. Then, they can also get really worked up when they are hormonal and scream at a dark corner for hours if I let them, so in that case I try to stop then by distracting them or something.
