Answers (1)
My cats are indoor only cats. When they're looking out the window and they see a bird, they get weird. They crouch like they're going to pounce, and they make this noise... it's hard to describe, but if my cats were trying to imitate the rat-a-tat-tat of a machine gun, that's what I'd expect it to sound like.
they make this noise out of a) Anger b) Frustration c) Fear or d) Something Else? It's so sad to see my weird little babies sitting at the window making that noise at the birds outside! When Muffin was only 2 or 3 months old and an only cat, I once saw her make that sound at a cat she saw outside. I haven't seen her react like that to another cat since we added PC to the household.
Yes this is all cats psychology to make noise by seeing bird whether it is any cat
My cats are indoor only, too. But when I was a kid we had outdoor cats who still made that weird noise, and still managed to kill some of the birds.