You are here:

Canine Behavior/dog aggression


I rescued Hiro about 7 months ago. The rescue said he was about 8 years old and is 4.3 pounds.  He had a double ear infection, blind in one eye, double eye infection, and kennel cough.  After those all cleared up he had 10 teeth removed that were infected.  After all of this (and during) and was the sweetest dog and so loving. He goes to work with me and my business partner every day.  We are in the car at least 8 hours a day.  Hiro loves my business partner (who is male, I am female) and always cuddled up with him and played with him.  Over just the past week and a half, my partner was holding him in the car and Hiro bit him in the nose.  There was nothing my partner did to provoke him. After that, Hiro was fine with him for about 4 days.  During those 4 days, my partner was feeding him new treats that it turns out he was allergic to.  Hiro got diarrhea for a few days and had some accidents in the car. After he is noe physically feeling better, Hiro is growling at my partner whenever we are in the car and especially when he is being pet by my partner.  He snaps at him and tries to bite. He has never snapped at me or growled at me.  He is only getting upset at my partner and only whe when he's in the car. Until today.  Now he is growling at him outside of the car when he talks to Hiro and pets him. All of these times he has been growling and snpping, he hasnt been provoked.  He looks at my partner sideways, his ears are back a little, and his lips curl a little. He isn't being provoked or anything and the change was sudden.  The strange thing is when I am at my apartment and my partner comes over in the morning, Hiro is so excited to see him. He jumps around, wags his tail, plays, and is all over him. I am not sure what causes him to act aggressively and scared in the car, but mostly fine outside of it. My partner and I had an argument in the car with the dog and my partner was yelling at me. I'm thinking maybe Hiro feels he is protecting me? What can I do so Hiro stops growling and snapping at my partner?

Thank you for your question and thank you for taking on a little guy who came with some serious health issues. I'm glad you were able to help him get healthy again.

So... you describe Hiro's body language in the car (directed at your partner) as, "He looks at my partner sideways, his ears are back a little, and his lips curl a little."

That body language says FEAR to me. Fear signals include many body language cues such as looking sideways - turning the head away, but keeping the eyes on so that we can see the whites of the eye showing (this is called whale eye). Ears pinned back, tail tucked, body rounded with the bum and/or head closer to the ground than the mid spine, hackles may or may not be raised (this is the hair along the length of the spine and it could be raised at any location along the spine and tail), eyes may be like big round saucers with the pupils dilated, or they may be elongated (almond shaped) as the dog keeps the eyes half closed. Frequently the dog may show all his teeth, with the lips pulled back so that both front and side teeth are showing (though a milder version may be a lip curl showing just one part of the teeth such as just the right canine and a few teeth behind that). The dog may growl, bark, lunge and snap at or full-on bite when afraid.

You said that you and your partner had a yelling argument in the car in Hiro's presence. Was that shortly before Hiro began acting this way toward your partner? Or was he already showing signs of fear of him prior to your argument?

Dogs can be very discerning. it's entirely possible that Hiro has learned that in your apartment, your partner is always safe and this is why he's excited to see him there. But in the car where the argument happened, Hiro may not trust your partner now and so is showing signs of fear toward him. I know we all wish that our dogs love us so much that they are protecting us. But Hiro's body language as you describe it says he's trying to protect himself - not you. He's acting fearful, not protective.

At this point, I expect that the fear is becoming a bit generalized and he's now unsure if your partner is safe once they are both out of your car.

I would encourage your partner to NOT stare directly into Hiro's eyes. Looking at him nicely, and briefly if fine. But staring for long periods of time is considered a confrontation in Dog Language and so just that can be causing Hiro to remain fearful of him. Also, presenting his body fully square to Hiro is also confrontational to dogs. Instead, your partner should present shoulder-first so that he's in partial or full profile to the dog as this is less threatening. He should whisper and possibly use a slightly higher than normal pitch to his speaking voice as he engages with Hiro (think baby talk, without getting right up in his face). The most important thing is that your partner doesn't force his presence on Hiro. Let Hiro decide if he wants to come close to your partner or engage with him. Hiro should be restrained in doggie car seat and connected by a body harness to the restraint strap that doggie car seats have. He should be in the back seat while your partner is in the front seat. Your partner can glance over at him and can toss a treat here and there or offer a treat a few inches away from Hiro - giving Hiro the choice to move close enough to his hand to take it, or the choice to NOT do that.

I would also encourage that going forward, arguments are had at normal speaking volume and if possible, outside of Hiro's view/ear shot. Even if you're not yelling, the tension between you will be palpable to Hiro and this will only serve to make Hiro more fearful of your partner.

I encourage you both to read through the book, On Talking Terms with Dogs - Calming Signals , by Turid Rugaas. It walks through a host of subtle behavior signals that dogs give when they feel nervous, insecure and fearful. Some of the behaviors are things we can do in the presence of the dog to help the dog feel better because they are seen as "cut-off signals" designed to reduce tension and avoid conflict. So when we do those things in the presence of the dog, we are essentially saying, "I don't want a fight with you."

There's a companion DVD if either of you are visual learners. I encourage reading the book first so that as you watch the video, you have descriptions and definitions in your head as that should help you recognize the behaviors as the dogs do them.

You may also need to enlist the aid of a local positive reinforcement, fear-free/force-free trainer to help identify things that your partner may be doing that are causing Hiro to continue to be fearful. Recognizing subtle behaviors, body movements, gestures, tones of voice, etc. that your partner may not even be aware he is doing will allow you both to adjust the interactions so that Hiro can feel safer in his presence in the car.

You both may need to take the time to counter condition Hiro to your partner's presence in the car to change his current emotional response back to a more relaxed and trusting one. The local professional will be able to help you work out a specific protocol for you and Hiro, and will help you both learn how to time treats correctly to make a positive change (timing is critical, if the timing of the treat is not correct with relation to the interaction with your partner, we can actually cause greater fear of your partner AND fear of the treats...). An introduction to the process/concept of counter conditioning can be found in books like:

Nicole Wilde's Help for Your Fearful Dog: A Step-by-Step Guide to Helping Your Dog Conquer His Fears

And Patrica McConnell, PhD's book, The Cautious Canine - How to Help Dogs Conquer Their Fears

The most important recommendation I can make in this forum is: Patience and Space. Be patient with Hiro and provide him sufficient space so that he can feel comfortable and decide when/if he wants to engage with your partner. Don't force him to sit in your partner's lap. Don't force him to rely on your partner at first for potty break walks, etc. Give Hiro a chance to regain some trust in your partner after the yelling argument and don't give him any reason to further fear your partner (no more arguing in front of him). He's a sensitive pup, clearly, and very attuned to the emotional state of both you and your partner.

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

Los Angeles Behavior Specialist  

Canine Behavior

All Answers

Answers by Expert:

Ask Experts


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.

©2017 All rights reserved.