You are here:

Canine Behavior/fear aggression


Before I adopted Jerome he was a happy, easy going dog that attended the doggy daycare facility I had just started working at. He got along well with all other dogs of all sizes. Then came a small dog with big attitude named Hercules. Hercules had an issue with other dogs. If they got too excited, played too rough, moved too quickly, etc he would run behind them nipping their back legs. This behavior occurred over the course of a couple days as Hercules was boarding with us but in decreasing occurrences. One day the pack got very excited as it was towards the end of the day and a lot of dogs were getting picked up. Hercules targeted Jerome for his nipping behavior. He bit Jerome's hind leg and Jerome had enough. He turned on the dog and really went after him. After this incident Jerome's behavior changed. Anytime the pack would get really excited, Jerome would immediately run to the fences (the daycare was divided into three sections with vinyl privacy fencing) and start fence fighting. He didn't go after the dogs in his run, but it was always a great fear. Skip ahead a couple months and Jerome's behavior hasn't improved, but I have adopted him and neither of us is still with the daycare. He is getting plenty of exercise and lives at home with two other dogs (one larger and one much smaller than him). He gets on perfectly with them and never triggers when his little brother barks, growls, plays rough, etc. The issue though: anytime we are out and Jerome hears a smaller dog barking he goes into fight mode. Pulling on the leash, barking, growling, the whole nine yards. I have a very hard time calming him down and getting his focus back. For the immediate time after it seems that he sees anything outside of his family as a threat. Please help!

Thank you for your question. It's unfortunate that Jerome had an increasingly frustrating time at doggie daycare, which culminated in a need to defend himself against a dog who really shouldn't have been in daycare at all. And now you and Jerome are facing the consequences of that.

I commend you for taking Jerome out of daycare as it would only continue to be an unpleasant experience for him. It's great that he gets along well with his new housemates, but it's not surprising that he continues to be untrusting of dogs he doesn't know. Kudos to you for seeking out options to help him feel safer when out in the world.

I strongly encourage you to seek out a force free/fear free trainer who is familiar with counter conditioning and desensitization techniques to help you learn to help Jerome regain his confidence when in the presence of new dogs. Note - he may never be a true social butterfly again. But we can help him feel safe enough that he no longer feels a need to defensively explode every time he sees an unfamiliar dog.

Along with looking for a positive reinforcement trainer to help you learn the nuances of helping Jerome, I also encourage you to read the following books...

Behavior Adjustment Training 2.0: New Practical Techniques for Fear, Frustration and Aggression , by Grisha Stewart

This book will teach you some great force free techniques designed to empower the dog to learn that he can choose to engage or choose to not engage so that he is in control of interactions, thus making him feel better about those unexpected encounters.

Feisty Fido: Help for the Leash Reactive Dog , by Patricia McConnell & Karen London
This is a more classic walk-through of Classical Counter Conditioning. You may find the tools in this book more to your needs in some situations.

Also, to help you be better able to read Jerome's more subtle signals of feeling uncertain, concerned or fearful so that you can help by intervening at those earliest warning signs, rather than waiting until he feels he must defend himself, I encourage you to read On Talking Terms With Dogs - Calming Signals , by Turid Rugaas.

This book will help you learn to read many very subtle cues such as lip-licking, squinting eyes, and even yawning, and what they might mean in various contexts, which will allow you to help Jerome before he becomes defensive.

You can search for force free trainers at the following links:

Certified Professional Dog Trainers (CPDT)

Association of Professional Dog Trainers (APDT)

Pet Professionals Guild (PPG)

Or you can search for more advanced professionals:

Certified Applied Animal Behaviorists (CAAB)

Veterinary Behaviorist

When looking for a professional, please ask questions about their approach and methods. You want to avoid working with people who utilize aversive tools such as choke chains, pinch/prong collars and electric collars. You want to avoid working with people who use aggressive methods such as poking or kicking the dog, yanking on the leash, and so-called "alpha" rolls or forced submissions. These tools and techniques have been demonstrated repeatedly through scientific study to have a great deal of behavioral fallout, usually in the form of increased fear and aggressive displays (though sometimes the dog will shut down and stop offering any behavior. This latter response is sometimes viewed as "success" because the person doesn't understand the difference between suppressing behavior and modifying the emotional response to the trigger).

Instead, you want to look for people who focus on setting the dog up for success by always working to keep the dog below his reaction threshold. They will use food, toys, play and affection to reward the dog for behavior choices that we would like the dog to perform more (rather than correcting the dog for failing to do what we see as "better" choices). They will talk to you about counter conditioning, positive reinforcement and desensitization.

The American College of Veterinary Behaviorists put out a PDF handout on how to select a trainer. You can view that here:

Finally, if a trainer ever does something to your dog, or asks you to do something to your dog, that makes you feel uncomfortable, do not hesitate to stop the session and discontinue working with that trainer. You are your dog's advocate and his voice. He's counting on you to keep him safe.

It will take some patience to help Jerome through this issue. But he will almost certainly make progress if you use the approaches suggested above. Good luck! Please feel free to follow up if I can be of any further assistance.

Worcester, MA Behavior Specialist
Masters candidate - Animals and Public Policy (Animal Behavior)
Tufts Cummings School of Veterinary Medicine  

Canine Behavior

All Answers

Answers by Expert:

Ask Experts


Jody Epstein, CPDT- KA, APDT


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 5 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. 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 professionally modifying behavior and training obedience for 7 years. I have owned dogs my entire life. I have just changed the name of my business. It is no longer Good Dog! Dog Training. The new name is Nutz About Mutz!. If you see previous questions with the Good Dog! website information, that is my response.

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 graduate education in animal behavior and learning. (While I completed my coursework and did the requisite research, I did not defend a dissertation. I am qualified, but not certified and so technically not a doctor. This is commonly referred to as Ph.D.-ABD which means All But Dissertation.) My educational focus was with non-human primates, but my personal interest is with domestic dogs and their relationships with humans and other animals. I continue to educate myself to canine-specific behavior through extensive reading, online interactive workshops, vidoes and attending canine behavior conferences.

©2016 All rights reserved.