I approach screaming from a traditionalist's point of view. I see it exactly the same as Tom Smith above. If I use OC, I don't know it. And although I hear it talked about quite a lot, I can't say I've ever personally seen anyone do anything to a hawk with "OC" that makes me want to throw away or modify my methods. And when I saw this question posed, I thought to myself, "good, If these OC guys are really good, they will spell out how they can stop ingrained behavior such as screaming with OC, - and I'll finally be convinced." But I mostly hear a lot of lofty theory's and very little of something I can use from OC proponents. It's quite easy to just say "reward quiet behavior." But that sounds a bit like more theory. I'm not slamming OC, I'd just like to be shown and convinced it could help my falconry.

I do like people who can think outside the box. And I think I'm open to any new idea that hit's me upside the head. Roger's idea of "hunting" off the fist for hidden food instead of having it handed to the bird is a good example of someone thinking outside the box.

My approach to screaming has involved mainly 5 approaches (all very traditional):

1. The more into hunting and catching it's own food the bird becomes, the quieter it gets.

2. And this is related to the first - Time. Screaming subsides with age and time. And that's all about the bird becoming dependent upon it's own ability to hunt and kill.

3. Avoid direct and obvious food association as much as possible.

4. Extended time with the parents, if I really need a bird that is quiet. The longer they stay with the parents, the less likely they are to scream.

5. Constant contact with people verses contact with people only at feeding time. I have noticed for many years that my imprint accipiters scream less and stop sooner when they are kept in the house and around me all the time. Birds kept outside in an outdoor mews scream more and take longer to stop.