Hi Lindsay.

there is a lot in your post to respond to, and I keep trying to tackle all of it at once. Maybe I should go for pieces.

In advanced animal training theory there are two basic approaches to extinguish a behavior - train an incompatible behavior or put the behavior on cue and never give the cue. That second approach does not actually completely extinguish it by itself though, especially with something an animal has a strong natural urge to do (self reinforcing) and screaming is definately in that category. Although, I do find it very handy to have a hawk that screams on queue in the field - no telemetry is required at short ranges. A second downside to that second approach is that under the very best conditions it will increase the occurance as the animal is being directly rewarded for the behavior for a period of time, and in the worst conditions you will increase the occurance permanently.

I am going to go out on a limb, and assume you are going to decide with the first approach and train for an incompatible behavior. The simplest of those to latch onto in this case, is silence. A hawk cannot scream while it is not screaming, so that is a bit of a no brainer.

Like all other Operant Conditioning projects, the sketch-up for how to shape away screaming is pretty simple, and would fit on a post it note.

First, you should have a firmly established CR, and have done some other shaping games. I would not start off with this one to establish a CR, but if your very good at CR timing you could pull it off. Also, you will likely need at least one of your established CRs to be remotely detectable (audible and delivered from another room, or a button that flashes a light remotely or something like that).

You mentioned that you have already noticed times when your aplamado is less likely to scream than others. That is your starting point. Do whatever it takes to catch him when he has been quite for as long as you think you can get away with. Perhaps perched in the apartment with a full crop while you are out of view. Figure out what the time span you have where he will be quite, and set up the criteria so that if he gives you at least 80% of that estimated max time, he gets a CR and a tasty tidbit. Initially if you ever notice he has gone more than 120% of the expected max time, give him a jack pot. Any time you deliver a tidbit reset the clock (either use a stop watch or keep track in your head if you can do so).

Most importantly - be certain of your timing. Just a few missed CRs, and you will be reinforcing the screaming instead of the silence that you want, and that will be very tough to overcome.

Keep your goals small to start with, and work up as you can. As you start making progress, the criteria for a jack pot should go up to. Jack pots are to encourage dramatic progress. Also, the likely scenario in the beginning is that you will get a scream as soon as you give the CR, because he will be excited about the coming treat. Accept that for a while, but as he really seems to understand what is being rewarded and make progress, add one additional rule: he only gets the tidbit if his vocalizations are acceptable to you from the time he got the CR until the tidbit got delivered. You may need to back off on this additional rule for a here or there if a long time goes by without being able to deliver anything, and if that is the case and you are able to catch him staying quite after a CR is given that would be worth a jackpot.

Now to give a real world example, this roughly what I did with the goshawk I am currently flying. I had initially put screaming on queue so I can find her on a kill in the field, but this has broken down and I need to go back and reestablish that. As I mentioned, putting screaming on queue made her an awful screamer around the home when she was at flight weight, and she is intermittent about screaming during the molt. If I have her inside my house she screamed incessantly. This year I decided that I missed having a hawk perched in the house and I was going to do something about it, and I followed the exact scenario I laid out above when I began reclaiming her from the molt because that is when she was still relatively fat, and least likely to scream. My initial criteria was 15 minutes of silence, and after about 5 days I was able to go for 40 minutes of silence even though her weight was coming down. In the beginning, I got my best results when I was in a nearby room out of sight (I would perch her just outside the door of my home office). I never got things so good that I had total silence, but she would only scream for the first 10 minutes of being put on the indoor perch. That is, until I moved to a house where I am not supposed to have her inside, and had to cut her weight down a lot to get her to go for ducks and jacks. IF I had been diligent I still would be there. The breakdown was not in the effectiveness of the technique, but in my resolve to stick to it.

And getting to your more general question: Screaming is usually about food, but in imprints they may scream for other reasons. Because they miss you, because they love the sound of their voice, etc. If your aplamado is screaming because he wants company, maybe you need to be hanging with him to catch him being quiet.