Ugh good to know, thanks guys. I tried to whistle to him and see if he would fly over to me, but he seemed a bit focused on finding something to eat in the grass.
Cockatiels usually live in pairs, small groups or larger flocks in the wild, so a single bird is more likely to be an escapee in our area. If you see it again in that area you could report it? Someone may be looking for their pet.