Why Would a Dog Suddenly Start to Bark at Other Dogs?

Many barking dogs are simply small and scared.
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One of the most embarrassing moments as a dog owner occurs when you find yourself holding on to the leash of a barking dog. All eyes seem to be on you to fix your dog's behavior ASAP. There are many potential causes for this behavior, ranging from fear to frustration.

Pinpoint the Details

In order to assess why your dog is suddenly barking at other dogs, it's important to pinpoint the details. Is your dog a puppy, adolescent or adult? Have they had any recent, upsetting interactions with other dogs? Has your dog had any surgeries or been ill? Have there been any major changes in the home like someone moving in or out? Sitting down and trying to consider questions like these is a great start to determining the source of your dog's behavior change.

Fear-Impact Periods

As your dog grows, he will go through two to three fear-impact periods. The first of these periods occurs around 8 to 11 weeks of age, and the second occurs during either the fifth month or late adolescence. During a fear-impact period, young dogs are especially sensitive to potentially scary stimuli. This includes frightening or inappropriate interactions with other dogs, barking and rough play. Because of the sensitivity of these developmental periods, young dogs who would otherwise bounce back can experience anxiety, fear and other social scarring from the event.

Nervous Nellies

In other cases, adult dogs may be nervous due to a lack of proper socialization as a puppy, particularly if the fear-impact periods mentioned above were not handled properly. The dog may have experienced trauma like a fight or attack. And in some cases, it's simply the dog's personality to be fearful. Many dogs who are labeled dominant are actually afraid and misunderstood. Over time, they learn that the best defense is a good offense.

Protecting Resources

Another possible cause of dogs barking at other dogs is the concept of resource guarding. This means that the dog is saying, "Back away! That's mine!" The item in question could be anything from a bone to the dog's owner. Dogs also learn quickly that barking at other dogs passing the house makes those dogs go away. This goes for dogs walking by when your dog is in the car or out on a walk with you, too.

Frustrated Greeters

Finally, if your dog has suddenly begun barking at other dogs, he may be a frustrated greeter. This is a term given by behavior professionals to a dog who was previously always polite and happy to meet others. Yet due to the constraints of life, leashes and not always getting to greet, these dogs learn to relieve their frustration by barking at others. Be careful not to reward this behavior by giving in and rushing toward the other, often unprepared dog. Instead, your dog needs to learn manners.

Be Sure to Seek Help

If your dog has developed a habit of suddenly barking at other dogs, it's best to seek professional help before the behavior develops into aggression. Qualified training and behavior consultants can be found through independent certifying bodies such as the International Association of Animal Behavior Consultants and the Certification Council for Professional Dog Trainers.