Same here - I never really pottytrained my birds (because of the unwanted behaviour it might cause like holding it in too long or forcing themselves to poo because it's the only way to get let out of the cage) but IF (and when) I get pooped on I let them know it is *not* appreciated.
"vuile poepert" (you dirty defecator)
So they more or less train themselves
(the 2 I have now as well as my 2 previous CAGs)
Of course I look out for the signs - Appie will do the traditional buttshake (being not too comfortable with flying yet) and some flapping, Japie will (most of the time) just take off from my shoulder and decorate the PCmonitor or the (floor around) cages.
Fun fact: if you have your bird on you it is SO easy to notice
Their feet will grow warmer when they need to go ( well before actually pooping)
it is really hard to miss once you start looking for it.
Of course I get pooped on because I get distracted, or because my birds are making a statement.
Both the CAG's let me know they did NOT appreciate having another bird around by completely "forgetting" they did not usually poop on me.
Things are getting more settled now- and the warnings etc. are back, the macaw is copying whatever they do and is now telling me to put her on her stand when it is time to "go".
So yes ...the birds are once again doing great in training their keeper
