Yes, I've done this. You can teach them to poop on cue (helpful if you're out in town with them) and/or to poop in specific places. It's a matter of anticipating when they are ready to go, putting them in an appropriate place, and then treating when they poop. Very similar to dogs really -- they only respond to positive reinforcement, not punishment.
Good Bird magazine (a training magazine) has an article with specifics about poop training in the current issue (Spring 2008). You can download single issues
here to avoid the single issue shipping charge.
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