Hallo bmsweb,
getting a bird to fetch a ball is really difficult.
There are only two ways IMO:
Fisrt, you have a bird that natirally volubtarily picks up a ball (or another thing) and you can c/t this.
Second, you lead your bord to the ball and give the same cue you give for touching the target dtick.
Step by step, the bird will touh the ball and then you have to wait wht it does if you do not c/t: Push the ball, pick the ball up...?
I got my male budgie, Twitch, to pick up the ball for a millisecond and then toss ist away.
His female, Keisha-May first picked up the ball on her own and was heaviliy reinforced by me for that.
She now takes the ball from m hand, flies away with ot, runs wround with it and, with luck, retirns it to my hand.
Twitch watches this a couple of times and now...flies on my hand and picks up the balll.....for a millisecond, and tosses ist away!
We have been practising this for 3 months now, and it has hardly improved, except that he noe sometimes returns the ball to my hand (i. e. pikcs it up from my hand and almost instantly drops it back).
The great rhing about that:
Both birds LOVE to "play ball" but will only do it when I offer them the ball; neither experiments with it on its own.
Best,
Frederica
P. S. Best way to start:
Put some balls around the playstand/ cage and wait to reinforce any activity with it.