Help, My Dog Bites! How to Deal with Dogs Who Bite

6 | Posted 5/21/12

Help, My Dog Bites! How to Deal with Dogs Who Bite

By Dr. Sophia Yin


My adopted Chihuahua, Chico, has come a long way. However, if anyone comes to the house or if he is outdoors and meets a stranger and he is on the ground, he immediately wants to attack, following several displays of barking and aggressive lunging. One time he did clip a woman's knee and drew blood. What do you advise for training Chico to be receptive to friendly people when he is outside and walking on the ground?

Gloria Aceti
Washington Crossing, PA


We just adopted a loving terrier that is loving and sweet.  Unfortunately, she exhibits extreme aggression at times. She does not do well with visitors coming into the house, and refused to stop barking and nipping at them.  We encourage our guests to give her treats upon arrival, at the suggestion of our vet. We tell her NO firmly and attempt to grab her snout when she behaves this way, but nothing seems to work! She’s also aggressive when we try to wipe her feet. What do you suggest?

Reluctant to Return our Rescue Dog
Rocklin, CA


Some people may read these descriptions and assume that these and other dogs who bite are just mean, but it turns out the most common cause of aggression in dogs is fear. It’s not fear brought on by abuse, but, rather, fear that developedbecause these dogs failed to receive the amount of socialization they needed starting before three months of age and continuing into early adulthood. Even fromthe short descriptions above, the telltale history is there. These dogs quickly got used to their adoptive families within a few days or weeksbecause it’s easy to get used to people who are constantly around them; but new people who pop into their lives fleetingly are another story.

Once Fear or Reactivity is Recognized, Take Action Before the Behavior Progresses to a Bite

Generally fearful dogs start off by trying to stay away from the things that scare them. But as they are confronted with scary situations repeatedly, they can learn that offense (barking, snapping, biting) is their best defense because it makes the scary people go away.

To see the body language of fear/anxiety, see Dog Bite Prevention Week: Poster on Body Language of Fear and Aggression and Dogs Bite When Humans Greet Inappropriately.

Treatment of Fear, Reactivity, or Aggression Focuses on Two General Approaches.

One approach to dealing with fear and aggression towards people is to train the dog to associate unfamiliar people with good things in a systematic/graded manner. This process is desensitization and classical counterconditioning (DS/CC),and it involves exposing the dog to the fear-inducing “stimulus” at a level where she barely responds and keeping her in a happy state, instead of a fearful or reactive state, by pairing the experience with things the dog likes (such as food, play, toys). The goal is that, as we systematically increase the level of the stimulus (how close the people are, how quickly they move, or how scary they look) while keeping Fido in a happy emotional state, the dog will systematically come to associate the scary people with this positive emotional state permanently.

Now, a lot of people try this method and have only partial success because they omit a few vital points.

  • The first is that you must stay below the level of scariness where Fido barks, lunges or has any major reaction. This is referred to as staying below threshold. That usually means that the visitor must pretend Fido doesn’t exist. That is, stand sideways to the pet and look away as if the visitor is actually ignoring Fido even though he’s tossing treats. Ideally Fido just looks like he’s happy to get food.
  • The second key point is that the food or fun thing must be occurring the entire time the scary person is near. For instance, if the scary person is tossing small treats, the treats must come at a rapid enough rate that Fido doesn’t have a ton of time in between treats to decide that he’s still scared. Usually that means starting with treats coming rapidly at first and then slowing the treat rate down.
  • Treats also have to continue long enough so that Fido decides that the person is safe. That may take just a minute or it may take several visits, depending on Fido. In the latter case, when the visitor is running out of treats, the dog should be removed from the room or the visitor should leave.
  • The visitor also must make sure she doesn’t move too close too quickly or move in a quick or threatening manner since these can make the dog react defensively (e.g. going above threshold). (For tips on how to approach correctly so you aren’t accidentally threatening: refer to the How to Greet a Dog book and poster)

The second method for modifying behavior is to train dogs to perform appropriate replacement behaviors that are incompatible with the fearful behavior. This is called operant counterconditioning. The replacement behaviors we train must be ones the dog enjoys so that Fido is at the same time learning a positive association with the situation. For instance, when a dog is fearful, we can train the dog to focus on us and engage in fun behaviors such as heeling and other focus games that we have taught through reward-based training. Why do we have to be careful to avoid methods that use force or punishment to train or maintain the replacement behaviors? Say we train the dog to focus on us so he doesn’t bark or lunge and we do so using choke chain or pinch collar corrections. The dog may learn to focus but will do so out of fear of getting a correction. As a result, the dog is not likely to develop a positive association with the scary person/object/environment. The dog may outwardly look more controlled, at first, but side effects such as greater reactivity and fear are likely to occur in the near future. The dog may hide that he’s scared or that he wants to react, prompting us to put him in a situation where scary people are even closer to him. Then, at some point, he might not be able to contain himself and may break out in a reaction more severe than before.

As with the DS/CC we described in method 1, always start at a level where you can keep the dog happy and focused on you, keep the dog focused the entire time, end the session and remove the dog from the situation before he’s tired or you run out of treats. The better your technique and ability to train in a systematic fashion the faster the training will go. Technique is the difference between taking 10 minutes and 10 months to see a huge change. (For more information on technique, read Dog Training Classes Can and Should Be More Than Sit, Stay, Stand)

To learn more about:

Understanding How They Learn and The Principles that Guide Learning (Timing, Motivation, etc):

Why We Tend to Avoid Punishment and Aversives and Dominance Theory

Treatment Must Also Address Impulsivity

These general approaches are pretty straightforward and, with good technique, you can get dogs through situations relatively easily. However, it turns out there’s more to these situations than just using the DS/CC techniques in the reactive situations. In fact, the first thing that we often have to do is address the dog’s impulsivity (lack of impulse control) and his lack of ability to look to the owners for guidance, especially when he’s scared or highly excited. How are these things important? Impulsivity is the tendency for animals to perform behaviors without first thinking and evaluating the situation. Dogs with high impulsivity or low impulse control tend to rush towards items they want (food, people, dogs) and react in an extreme manner when excited (jump, whine, pace, bark, lunge). The more they practice acting impulsively, the more likely they will react impulsively when scared. These dogs also have an inability to look to their owners for direction, especially when they’re scared or distracted.

Luckily, one program can address both of these issues. In my version of the Learn to Earn Program where dogs are required to automatically say “Please” by sitting for everything they want – every bit of kibble, petting, praise, attention, getting their leash on, going out the door—dogs learn that they can have what they want if they ask politely by sitting and looking at their owners for permission. In this intensive program, dogs can exhibit huge changes within a week. The trick is that the humans need to learn to reward the dog’s good behavior consistently and must be aware of their every interaction so that they don’t accidently reward unwanted behaviors, such as jumping, whining, and pushing for attention. So, at the same time, this program teaches owners how to give the right body signals and cues that their dog naturally understands and how to actually provide leadership and guidance through skill rather than force. As an added benefit, once owners have these skills they are better bonded to their pet and their pet feels more comfortable looking to their owners for guidance in the scary or highly exciting situations.

The Step-by-Step Approach:

Now that you know some of the general approaches. Here’s the basic order of approach.

  1. First, keep safe: avoid all situations where the dog is fearful or aggressive until you have gained the skill to work productively in these situations. And when you do work with your dog with visitors and unfamiliar people present, you may choose to avoid having the visitors or unfamiliar people give your dog treats. It can be unsafe to rely on other people to give treats because the visitor may do something inappropriate such as moving too close, staring at, or suddenly trying to pet the dog. Or because they toss the treat too closely to themselves and the dog comes closer and then realizes he’s too close for comfort and snaps. Instead, you, the owner, can give the dog the treats or have the dog perform exercises where he focused on you.  Also, it's best to have the dog on leash, even on a gentle leader, snootloop or halti head collar. Make sure you're holding the leash short enough that even if your dog does lunge towards people he can't reach them (e.g. he can only lunge a few inches). For added safety, some dogs will need to learn to enjoy wearing a muzzle. You can cut a hole in the front of the muzzle to give treats. (See Training Dogs to Love Wearing a Muzzle)
  2. Second, identify all other situations where your dog is fearful or highly aroused (e.g. uncontrollable barking, whining, lunging) and address these issues too.  This is important because fear of objects and other things can heighten fear of people. For instance, if your human-fearful dog gets scared of a loud noise or object in the morning and then goes for a walk, he’s more likely to react fearfully to people on his walk. Similarly if your dog practices rough, overly rowdy behavior, then, when he’s fearful, he’s more likely to display that fear with the same rough, overly rowdy behavior.
  3. Avoid the other fear and high arousal situations until you have the skills to modify the behavior in these situations. Generally you can gain some skills quickly and just start working in the situations at the distance or intensity that you can handle. For instance, if your dog gets scared around inanimate objects on walks, when you see the type of object he might bark or lunge at or run away from, you can work at the distance where you know you can keep him happy and focused on you.
  4. Take your dog through Dr. Yin’s version of the Learn to Earn Program so that you can systematically and quickly develop the ability to provide direction for your dog and so your dog can quickly develop the ability to control his impulsivity. Some dogs only take a few days to a week while others may take a month or two—the biggest variability is the human’s awareness of what they are doing. If owners could be 100% consistent in rewarding desired behaviors and removing rewards for unwanted behaviors, they’d have a nearly perfect dog in just a week or two but for many owners it takes weeks to become aware enough to be 80% consistent. The benefit of the Learn to Earn program is that even if you never reach professional level skill, you’ll still be way better at communicating with your dog and moving in ways that make your signals and intentions clear.
  5. DS/CC to the specific fear, reactive, and/or aggressive situations. Generally, this means going about your day in a normal manner, but, whenever you pass an unfamiliar person, you have your dog perform the fun heeling games so that he can focus on you while learning good things about the people that pass by. The better your technique, timing, and ability to use your body movement to help keep the dog focused on you, the more successful and efficient you’ll be. Similarly when guests visit, set the situation up so that you can keep Fido focused on performing replacement behaviors and then you separate him from the guests if he’s not completely comfortable and under good control.
  6. Also, DS/CC to any handling type procedures that are an issue: In many fear or reactivity cases, the dog is also difficult for being handled in certain ways (such as for toenail trims or grooming). Generally I recommend starting with classical DS/CC where the owner pairs the procedures with food and then increases interval between food until food is no longer needed (See Training a Dog to Enjoy Toenail Trims). Once less food is needed, I often switch to rewarding a specific behavior such as holding still for 10 seconds while being groomed and increasing the amount of time the dog must perform the good behavior to earn the reward.

This is the overall approach to the fearful or reactive dog in a nutshell. It’s all about addressing the dog’s overall ability to look to you for guidance, and your ability to be aware of his emotional state and to reward desired behaviors and remove rewards for unwanted behaviors. Because the techniques do actually involve skill and technique, unless your dog is extremely easy, you will most likely need coaching. But now you’ll know what to look for and you’ll be aware of the common mistakes to avoid.

Comments Leave a Comment

Posted by .(JavaScript must be enabled to view this email address) on 05/22 at 07:49 AM

I used to have a dog who was a very curious case and I would love to hear some ideas regarding her behavior.
This dog was a female GSD and this behavior appeared for the first time when she was around 4 years old. Gioia was a very outgoing dog with familiar people and her behavior with family was typical GSD meaning she was social, playful, and attentive to us. She could best be described as aloof towards unfamiliar people, and she was around many, at the dog club and in competitions. She worked happily, played happily, and showed no signs at all of being uncomfortable around any person. While she did not solicit attention from unknown people she did not avoid them and she showed absolutely no concern about them, no matter how many were crowding her (at shows for example) or how strange they looked, sounded, or acted. She also showed limited curiosity about new folks, she might notice someone new if she was in a context where known people out numbered unknowns (such as the dog club) but when she was surrounded by strangers at shows or at the pet store she had no interest in sniffing them or whatnot.
In all cases she seemed relaxed and engaged in her work or her environment.

Sometime when she was around 4 years old I had her at a meeting of GSD fanciers of different types and my neighboring person (we were seated at long tables) was one of those people who just insist that they can make friends with every dog. I told her that this dog (who was laying down by my chair) had never had any interest in making friends with casual strangers yet she persisted in making friendly overtures and touching Gioia. After a few minutes Gioia went up and laid her head on my neighbors lap and and allowed her head to be stroked for a few minutes. At some point (seconds, minutes, it has been so long ago that now I do not remember) Gioia bit the lady on her non petting hand. Gioia bit her just hard enough to make her jump (there was no damage to her hand) and for all my life I think Gioia smiled and laughed. She was relaxed and happy through the entire incident and after it was done she play bowed, bounced, and then laid back down at my feet.

This pattern would have repeated if we had not changed how we handled Gioia. After what we called "The Sucker Punch" indecent we were more aggressive in preventing well meaning people from attempting to interact with her. This was not difficult and we continued to compete with her, train her at two dog clubs, and show her.

After the Sucker Punch Incident I think Gioia actually decided this was a fun activity and if we were not extremely careful she would give all type of solicitous behavior in an attempt to get strangers to come up to her, she would then bark and/or snap at them, watch them jump back and start her play bowing happy dog behaviors again.

In the moment of her aggressive behavior her facial expressions were not mixed, she had a very hard eye, forward ears, and an offensive pucker. I could not detect any ambivalent or fearful signals like hackles, snarling or showing any teeth, whale eye, or pulled back mouth. After each incident her expressions were also not ambivalent she was relaxed, loose with a soft eye, ears and mouth. For all the world it seemed as if this was a really fun game for her. I had many people tell me this was a fear behavior but nothing in her affect seemed at all fearful. It seemed the most like how she would get a reticent or challenging sheep or goat to move.

But again, we were careful with her and so in grand total there were only a very small number of incidents, none of which ever resulted in any contact (excluding the first one) or injury. Only 1 time did Gioia injure someone and that story follows.

The only other aggressive behavior we had with Gioia was at our agility club. Our coach wanted to reset Gioia's hind end onto the teeter and he did something he had never done before with Gioia (or any dog) and he grabbed her around the waste to reset her hind legs. This took me and Gioia by surprise and while I froze Gioia did not, she spun around (in mid air it seemed) and bit him hard, very hard, and shook him a little and then let go. No barking, growling, or any warning at all. He grabbed her, she bit him, and she let go. It took like 1 second. He flushed out his hand and continued teaching and we working. Gioia worked happily and as she always did in agility and she showed no signs of being traumatized. She really did not care for my coach after that and while she never showed any aggressive behavior towards him again (and he never grabbed her again) it was obvious to me that she really found him aversive if he wanted to interact with her. She would go hard and still. She was not worried about him unless he wanted to "make up" with her, as long as he was indifferent she was her typical self. I am not sure how this was related to her previous behavior.

Gioia lived a long live, earned many titles, and aside from this behavior she seemed a normal and well adjusted dog. She traveled extensively, worked hard, and enjoyed a long and full life. We loved her and her us and I think having her taught me much about behavior but I have not yet been able to come to any better idea as to her motivation than she found scaring people to be reinforcing. I would love to hear other people thoughts.

Posted by .(JavaScript must be enabled to view this email address) on 05/22 at 01:48 PM

We have a 3yo Yellow Lab who is severely fear aggressive. He has bitten both my husband and myself on several occasions. Luckily, we are the only ones he has bitten so far...He accidentally had ocassion 3 times to bite people but he either just "barked in their face", or just grabbed clothing. Once he gets stressed, he completely and totally short circuits and will bite anything and anyone in his way. We obviously keep him leashed at all times...he is now in a prong collar which has helped us control him quite a bit. We leave the leash dragging behind him now so when someone comes to the door (completely freaks when this happens) we can at least get his leash from the safety behind him.

I was bitten most recently and it was actually interesting. I heard a crash outside and looked to see one of our horses had gotten in with my 2 blind horses and one of those is my 36yo first horse whom I am very protective of. We both jumped up and grabbed shoes to get outside. I ran out the door first and left it open so Rio trotted out behind me. I hooked him up to a tie out line which was handy. I am watching hooves flying all around my ole timer and in that split second decide it would safer for the dog in the house so I just went to unhook the line (all the while watching my horses) and he bit my hand VERY badly...my whole hand was in his mouth and he bit down hard!!! Rio had not been barking or doing anything audible to me to indicate he was picking up on our anxiety and adrenalin rush so I was paying him no attention at all. Prior to this, we hadn't been bitten in over 2 months so I guess my guard was down completely.

His stressors are other dogs on leash being walked (he does GREAT at a local day care- they took the time to start him off slowly but he now plays well with the whole pack), sometimes people coming near the car and people coming to the house. I can get him in a down and not barking from a distance...if we get too close to the strangers, he freaks. At times there is no quieting him and I have to completely remove him from the stressor.

We had his thyroid tested by Dr Dodds and at that time he was fine - will retest yearly tho because his mother has thyroid issues

95% of the time this dog is relaxed, playful, mischievous and loving....but the rest of the time is quite challenging for us! Any advice will be appreciated. Thanks

Posted by .(JavaScript must be enabled to view this email address) on 05/24 at 01:48 PM

I had an experience similar to Susanne's with a Standard Poodle. He was an adolescent at the time and we had moved from Maine to Georgia. They must have some mean dogs down there as several people would see us coming and before I had time to move my dog off the sidewalk literally jumped out of the way and crossed the road. Linus (the poodle) apparently thought This was a game and actively started to look for people. Fortunately preventing rehearsals and a little CC did the trick. Linus was also a very calm, confident dog who showed in Utility and did countless demos for schools etc... Other than this brief adolescent "hobby" he was always friendly and easy going.

Posted by .(JavaScript must be enabled to view this email address) on 05/24 at 07:39 PM

I find your blog informative since I have a golden retriever at home.Keep it up!

Posted by .(JavaScript must be enabled to view this email address) on 05/27 at 10:15 AM

I have a very loving, playful and intelligent black lab. He's like any normal dog with me and my other dog and does well with other dogs in general. With people he is a nightmare. He had a very bad start in life, having been quarantined at birth due to a Parvo outbreak and then , at eight weeks old was attacked while sleeping. Another dog tried to kill him. He hid for a week and would only come out if held. He wouldn't come out for food either, including raw meat.
I could write pages about his behavior although through years he has come a long way.. He just can't be around other people.It takes him weeks to "warm up" but when he does, he's adorable. He is now six can go out and play and will still bark at people.I don' tallow him to be approached and a stranger can come within three feet but only if they ignore him. He used to get hysterical running in circles, barking, air biting and he would then hide behind me. In the beginning he would just freeze and look at the ground. Now he barks until he's too tired to bark more and then he just stands still in place just watching and panting. That's not to say that he wouldn't react if someone tried to pet him.I just don't allow it and it kills me.
He doesn't know the happiness that come with having the "life of a dog".

Posted by .(JavaScript must be enabled to view this email address) on 06/15 at 03:10 AM

I have a question , every time I coammnd my dog to sit , he obeys and sits, but when I give him the treat he paws with one paw and won't let me give him the treat , it's like he wants to snatch it from my hand , I always have the treat firmly gripped with my thumb on top and my index holding the treat on the bottom so it won't get snatched from my fingers, how do I get him to stop pawing me when I give him his reward? so I grab one paw so he won't lift the other while praise him 4 the mean time

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