When a dog is afraid, it reacts by trying to escape, hiding, acting aggressively, or becoming immobile. Dogs with a particular phobia to noise usually try to escape or hide. In this process, they may injure themselves or damage property by digging and chewing. Dogs that succeed in escaping may run long distances and become lost. Some dogs have become stuck within their hiding places as a result of wedging themselves in so tightly.
Noise phobias range in severity from mild to severe. Dogs that are mildly afraid may only pace and pant. Dogs that are severely phobic literally panic. Such dogs have chewed through walls, ripped up furniture and automobile upholstery, and even jumped through second-story plate glass windows.
Dogs that are afraid of thunder often begin acting fearful before the owner is aware of the impending storm. Perhaps this is because the dog can hear the thunder sooner than the owner can or because it has learned to associate other weather changes, such as an overcast sky or rain, with the sound of thunder.
Dogs do not outgrow noise phobias; in fact, the phobia gets worse with time, with each exposure to the sound leading to increasing fear. Additionally, the fear tends progress so that it encompasses other similar sounds. For example, a dog that is initially afraid of gunshots may eventually become fearful of the sound of backfiring automobiles.
