I adopted a new cat a week ago - Bear, a 3-year-old neutered male. He's been confined to the spare bedroom for the past week, and occasionally I'd let one or two of the other cats in to visit with him. But today for the first time I kept the door open. All was ok most of the day - the dogs went in and out a few times (mostly to see if any food had appeared in the bowl). I went to sit on the bed with Bear for a while, and Henderson (4-year-old male cardi) sat on the floor, staring intently at the cat. Kind of freaked me out, because I'd never seen him with such a predatory look in his eyes. Then he jumped up on the bed to sniff him. After a minute or so, Bear hissed at Henderson - that's when the barking started. I took Henderson out of the room & closed the door again. Then he alternated patrolling around the closed door with coming to look at me (as if I were going to open it for him!). Now he's back to playing with his toy in the living room (stand-in for the cat?). He gets along with all my other cats, but the thing is, they were here first. Is this a territory thing? My 2 greyhounds are pretty much ignoring the new cat. I know corgis are more territorial than greyhounds. Will the "no kitty!" I used with the greys work in this situation? Giving him a treat if he's quiet around the cat? Any suggestions or insight will be greatly appreciated!!