Cat Tail Language: 10 Secret Messages Your Cat Is Sending You With Their Tail Chewy It looks like they are vibrating. When a cat's tail shoots straight up and quivers or rattles at the tip, it is the highest form of excitement they can show. It's a Why Do Cats Shake or Vibrate Their Tails? Vet Verified Reasons Explained Catster How to Read Your Cat's Tail Language Why Do Cats Vibrate Their Tail? This Is What They Might Be Signalling With It We Love Catz Cat tail signs: What your cat's tail tells you