Hey! I just got a Sun Conure, so I can't really testify to much except that in the 5 days I have him he used to screech whenever he wanted attention and now he will simply come out of his cage and sit on the top or chatter when he wants attention.
I also have a bachelors degree in psychology, so I think that, if anything, might testify to my experience.
That being said, your bird is obviously screeching because he wants your attention. I like to think of the bird like a toddler that is throwing a fit for attention. The LAST thing you want to do when your bird screeches is to give them a treat (corn) or to pay attention to them. What I did with my bird when I first got him was to ignore his screeching altogether and pay careful attention to when he didn't screech and make sure that if he was quiet for a while to go over and give him attention and foods.
If he screeches, ignore him. I mean, glance over and make sure he's not in danger or something, but for all extensive purposes, don't talk to him, don't look at him, and don't go near his cage, continue on as if nothing is happening. Then, as soon as he is quiet, go over and give him attention.
Likely what will happen is you will go over once he quiets down and he will start screeching again. As soon as he screeches when you're over there, say no once and turn your back to him. Remain turned around until he stops screeching for a good amount of time. I usually only reward him by turning around if he has been quiet for 10 seconds straight. If he keeps screeching for more than you want to stand around for, then don't stand around, walk away, do other things, etc. But remember to come back when he's quiet. And if he's quiet randomly throughout the day give him attention, don't ignore him when he's quiet and pay attention when he's loud. That's teaching him that screeching gets attention and silence doesn't.
BE CONSISTENT. If you do it one way the first time, don't do it a different way the next. I know how hard this is. You feel bad because you want to fix what's wrong, but your bird needs to learn that screeching doesnt solve his problems.
Also, never give your screeching bird extra food. If you are bringing over food and he starts screeching because he sees it, say no once and hide the food behind your back. As soon as he is quiet, bring it out again. Anytime he screeches, hide it again. until he is silent for long enough that you can get it into the cage. Also, if your bird's screeching gets really bad, you can take away something he likes such as a toy or his treat. Just make sure you give them back when he's been quiet for a considerable amount of time. My bird particularly loves his pellets, so when his screeching was really really bad once, I said no once, and took them out of him cage and walked away with them. He got VERY angry. Climbed ontop of his cage and screamed at me for five minutes, but I didn't give in and waited until he was quiet, then brought them back saying good bird.
When your bird screams, don't ask him what's wrong, don't go over to him, don't coddle him and don't give him treats. Let him scream it out. I know how hard this is. Both on your eardrums and your heart, but it's the only way he will learn. The corn and attention you give him is like chocolate for a little kid. You wouldn't give a toddler chocolate every time they started throwing a fit and screaming or they would throw a fit and scream all the time. Same goes to your bird!
Sorry this is so long! Hope it helps!
