Common Rabbit Postures, Behaviors, and Vocalizations Purring or tooth purringA sound made by lightly and quickly grinding and vibrating the teeth as the whiskers quiver; a sign of contentment. Oinking or honkingA Why Is My Rabbit Shaking? Causes & Emergency Signs Our old bunny bacon did something weird yesterday. We were hanging out and his butt started vibrating VERY fast. Kept doing that as he stretched out. few seconds later he stopped and Rabbit Behavior Explained: Why They Thump, Flop, and Zoom Small Pet Select U.S. I was petting my bunny, just petting and holding his ears gently in my hand while stroking it, and he vibrated around his head area??? : r Rabbits WHY IS MY RABBIT THUMPING ITS BACK LEGS? When a rabbit thumps, it's usually trying to tell you something important. This is one of their main ways to warn others of danger