Ask A Vet: Why Does My Cat Twitch His Tail? You asked and we picked one question to answer this week: "Why does my cat shake her tail like a rattlesnake?", We've got the answer below from behavior professional Kenzie Korpela, IAABC SBA, CFVA. Why Do Cat Tails Shake and Quiver? Cats.com Why Do Cats Vibrate Their Tails? Reading Your Cat's Body Language Kinship Why Do Cats Vibrate Their Tail? This Is What They Might Be Signalling With It We Love Catz How to Read Your Cat's Tail Language and Meaning PetMD