What causes a cat to start spraying?

This page focuses on why cats might start spraying having not sprayed. This is a specific point.

Despite what some veterinary websites say, as far as I’m aware, there is no evidence which suggests that the medical condition of lower urinary tract disease causes urine marking. “Urine marking” means spraying. Spraying is not innappropriate elimination in a strict sense because its purpose is not to eliminate urine but to mark territory on a vertical surface. Innapropriate elimination is often caused by medical problems. Urine is deposited on a horizontal surface.

A research study by Pryor et al 2001a, concluded that the most common causes to start cat spraying are:

• Agonistic interactions with other cats in the same home or with a cat or cats outside the home. The word “agonistic” means aggressive or defensive social interactions.
• The introduction of a new cat to the household,
• Moving to a new home,
• Forcing an outdoor cat to become a full-time indoor cat,
• Cat’s owner is returning from a trip,
• A substantial change in the schedule of the household,
• The beginning of the cat breeding season.

As we can see, all the reasons are to do with the cat’s emotional state in one form or another. Stress and anxiety is often a motivator to mark territory and spraying is marking territory.

I am sure that there are other causes which can start cats spraying but in every case it will be a change to the cat’s routine and environment which creates anxiety which in turn leads to the need for reassurance which in turn leads to spraying.