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Canine Behavior/Dog being aggressive when told No!


My 8 year old Jack Russell/Beagle mix will start barking when he sees children playing outside or someone walking in view of the front window. My wife has been having migraine issues and his barking makes it worse. She has tried telling him No and even resorted to spraying him with water to get him to stop. It worked for a while but now he becomes aggressive and charges at her and shows his teeth and has to be confined to his crate. What can we do to stop him from barking and being aggressive when told no?

Thank you for your question. Though, I think the better question would be how can we help him feel comfortable with the happenings outside the window so he doesn't need to bark about it...

Management is key during the retraining process so that we don't provide him the opportunity to practice the behavior we're trying to extinguish. I would start by blocking his view of the window. This may be by closing the drapes/blinds, possibly moving furniture away from the window so he can't climb up and sit on guard duty, denying blocking the bottom half of the window to obscure his view or denying him access to that room.

Blocking the bottom of the window can be accomplished in a number of ways that are temporary such as taping butcher paper or black plastic garbage bags up. You can get sticky film from the local hardware store that create a frosted look to the window. Or you could even use bubble wrap cut to the size you need and then spray window cleaner up and stick the bubble wrap right to the wet surface. It will stick until you take it down.

Often, it's as simple as keeping the dog from seeing the things that are happening outside.

If he's responding to the noise, then we'll need to help him feel that the noises are predictors good things in his life. He's not barking to irritate you or your wife. He's not trying to make her feel worse and he doesn't understand that she's not feeling well. But, he does know that when he's telling you and her that there's a potential intruder outside (doing his job), he's being barked at ("No") and assaulted by the water. This behavior on the part of the humans is bringing out a defensive aggressive display in your dog. I'm not saying this to present any judgement, just to help you see the interaction from the dog's perspective. In order to change the dog's part of this conversation, you'll need to start by changing your half of it. . .

If we switch tactics and help him learn that the noises outside mean great things for him, you will find that he barks less intensely and for a shorter duration. This can be done simply by having a container of small treats handy. The moment you/he hears a child outside or a dog, tell him "Yes" and toss a few treats on the floor. Ideally, you're getting this in before he starts barking, but even if he has started barking, toss the treats anyway. You may need to start with super awesome treats like hot dog, cheese or chicken breast - whatever your dog loves best.

This initially is the process of classical conditioning - simply making an association for him that the sound of the kids/dogs reliably predicts the arrival of his favorite treat. Make sure he doesn't get that treat at any other time during this training process, only when there's a noise outside the window that's likely to make him bark.

For the first week or 2 or 4, you will simply drop a few treats every time he notices that there's kids/dogs outside the house. If the kids are playing for a while, you'll need to present treats frequently for the first several times it happens. So you may be dropping a single treat every 5 seconds, or a few treats every 10-15 seconds and then remove him to a back room and give him something to engage with such as a Bully Stick or an antler or Nylabone - some long lasting thing he likes quite well.

After a while, you'll start to see that he'll check in with you. He'll hear the noise outside, look at you in anticipation. If he gets no response from you, then he'll start to bark. At this point, we switch to operant conditioning - where he has to act in order to earn the prize. The action we're looking for is checking in with you (or your wife). So, now, when he hears a noise outside, he'll look at you. Mark the behavior "YES!" and drop a couple treats.

Once he figures out that looking at you is the key, he'll try it often. But only mark and reward when the criteria is met - kids/dogs outside and he looks at you without barking. Then, after a week or so of consistently working together like this, you can increase the criteria a bit at a time over a few weeks - he must look at you and be quiet for 5 seconds before you mark/give the treat, then 10 seconds, 20, 30, 1 minute, etc. Until he starts to learn that being quietly with you is the best way to get rewarded.

Two things are going to happen in this process. First - he's going to stop feeling upset about the kids/dogs outside because they reliably predict something great for him. Second, the quality of his vocalization will change from agitated to anticipatory and he'll shorten the duration.

Make sure, even when you feel like the behavior is dealt with that you still praise him and thank him for quiet, offer him cuddles or toys or games - anything he likes and periodically offer a food reward as well. This will help to maintain the behavior and avoid a relapse.

I hope this proves helpful. Please feel free to followup if I can be of further assistance.

Los Angeles Behaviorist

Canine Behavior

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Jody Epstein, MS, CPDT-KA


IF YOU BELIEVE YOUR DOG IS ILL OR INJURED, PLEASE CONTACT YOUR LOCAL VETERINARIAN IMMEDIATELY. THIS IS NOT THE FORUM TO ADDRESS URGENT MEDICAL ISSUES. I AM NOT A LICENSED VET AND HAVE NO DIAGNOSTIC SKILLS. ***I have been answering questions on All Experts for over 8 years now. I enjoy being able to offer assistance in this forum. I do need to be clear, though. If you’re looking for free advice about a specific behavior question, you MUST submit your question to me via All Experts. If you bypass All Experts and write to me directly through my website, I will ask you to submit via All Experts. On the flip side, if you’re local to Los Angeles and you wish to speak to me privately about an in person consultation, please go through my website. I appreciate your assistance in keeping my volunteer work on the volunteer site.*** I can answer questions about the following canine behavior issues: obedience, timid/fearful & fear-based aggression, nuisance behaviors, families that are expanding with either new human or new animal members and many other issues. If you have potty training questions please first read my trio of blogs at If you still have questions after reading the blogs you can post your specific questions here. PLEASE be as specific as possible when asking a question. Give me a detailed example of the situation - dog's behavior, body language, circumstances surrounding the issue, what the consequences are (another dog's response, your response), etc. I can only provide insight if I can get a picture of the whole scenario. If I ask for further details, please provide them. In person I would normally observe for at least 90 minutes to assess the situation and the dynamics before offering tools and suggestions to modify it. In writing it is ever so much more difficult. Thank you for your participation in the process.


I have been a professional obedience trainer for 9 years, and specializing in behavior modification for 8 years. I have owned dogs my entire life. I own my own dog training and behavior modification business called Nutz About Mutz.

I am a Certified Profession Dog Trainer - Knowledge Assessed (CPDT-KA), #2133301 ; I am a member in good standing with the Association of Professional Dog Trainers (APDT), #77763 ; I am an AKC certified Canine Good Citizen evaluator (CGC), #71253

Publications ; ; Multiple articles in the local pet magazine Pet Press (found across Southern California)

I have a masters degree (MS) in Animals and Public Policy, with a minor in Animal Behavior, from Tufts Cummings School of Veterinary Medicine. I also have 3 years of graduate education in Animal Behavior and Learning from UM-Missoula and UL-Lafayette. I continue to educate myself to canine-specific behavior through extensive reading, online interactive workshops, vidoes and attending canine behavior conferences, workshops and seminars. Beginning in March, 2017, I will be the Behavior & Training Manager at Second Chance Center for Animals in Flagstaff, AZ.

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