Cats shake or vibrate their tails for several reasons related to their emotional states and communication. Tail shaking or vibrating can indicate excitement, happiness, anticipation, irritation, or stress, depending on the context and the accompanying body language. For example, a cat might vibrate its tail when it is excited to see a favorite human, as a form of greeting, or when it is preparing to play or hunt. Conversely, tail thrashing or rapid tail movements usually signal annoyance or agitation. Cats also use tail vibrations during urine-spraying behavior as a territorial marker, sometimes without actually releasing urine, which can be linked to anxiety or insecurity. Watching the full body language and the situation is key to interpreting what a shaking tail means in each case.

Reasons for Tail Shaking

• Excitement or happy greeting
• Anticipation before play or hunting
• Mild irritation or overstimulation
• Territorial marking via urine spraying
• Anxiety, impatience, or insecurity
• Defensive or angry responses with thrashing tails

Thus, tail shaking in cats is a sophisticated form of non-verbal communication providing insight into their current mood and intentions.