He's landed on one's back and nipped her ears.
We had to move fast before the cat retaliated. If he's on my shoulder and I pick up a cat- any body part of the cat that gets near the bird gets nipped. He's nuts about it. No fear. He DOES NOT want those cats near him or anything he claims as his own. Personal safety doesn't seem to matter to him. Of course, with a brain the size of a pea, you can't expect much logic.... but you'd think SOME sort of survival instinct would kick in.
He nips strangers too. And us if he's in a bad mood. We have to lock him up when we have guests.
Like I said, *nice* for some of the time.