Canine Behavior/aggression


My name is kaitlyn and i have a question about aggression with dog to dog.
I just got a three year old blue heeler (female) and she is very aggressive towards my rottie great dane mix(male)
But he is fixed. She snarls and snaps at him of shes outside and come up to quickly at him., also she does the same if he is coming up the couch to see us and she is on it. She stops for a minutes but than shes right back to it. I find it strange considering she doesnt do it to my boarder collie(male) who is not fixed. He can basically come jump on her while shes on the couch or in her open door crate. She does not how ever really snap or snarl at the rottie mix when shes walking around the house. How can i stop her from doing that and why is it difderent for the two male dogs?

*** Thank you for the feedback. Yes, being pregnant makes a HUGE difference and changes the answer entirely. She is hormonal and moody and her body is sensitive and so she is very likely to have a shorter fuse for a pushy dog. And I expect that your intact male is the father and so there may be a different bond there. Good luck. Please make sure those puppies are well cared for and find good, loving, committed homes. Make sure that your vet is in the loop and monitoring her pregnancy. She should be eating a high quality puppy food from now until she stops nursing the pups as she needs the extra nutrition found in puppy food in order to provide proper nutrition to her growing puppies. Happy holidays. Enjoy the adventure!***

Thank you for your question. Just like people, not all dogs get along with every dog they meet. There are a number of things that could cause your female to behave this way. Because it's occurring in very specific places (and not just when they're walking around the house), it suggests that it COULD be an issue of resource guarding. This is when a dog feels that they are in possession of a prized item and must protect it out of fear of losing it. So, if she's on the couch and the neutered male approaches, she may fear that he's going to take her spot - force her out. If she doesn't want to move, or if she feels that the couch is a prime location to relax, then she is more likely to be defensive and tell him to stay away.

If she also gets annoyed with him when he comes bounding up to her too quickly, she may feel that he is invading her personal space and so she's telling him to get back.

One thing that I want to be very clear about in this is that we DO NOT WANT TO PUNISH HER GROWL. This is really important. She is communicating her discomfort at his presence. So long as he respects that growl and backs off, then they are communicating to each other and by doing so, they are avoiding an altercation. If we punish her for growling, tell her no, scold her, put her in her crate or otherwise isolate her from the family for telling us that she's not happy, we end up teaching her to stop telling us. This doesn't mean she's suddenly OK with his behavior. It only means that she's learned that she gets in trouble for telling you. This leads to the "out of the blue" bite because she's no longer giving her warning signals. Growls are a great thing because they tell us what the dog is thinking and they give us an opportunity to help the dog feel better about the situation without having to escalate to a full blown offensive strike.

Why does she allow the other dog (the intact dog) to be all over her? She likes him. Is it because he's intact? Not necessarily, but she is clearly more comfortable with him.

Without observing the dogs, I can't begin to tell you why the dynamic is coming out this way. Perhaps the intact male moves slower or avoids direct eye contact or offers any number of other behaviors that tell the female that he is not out to have a fight with her.

I would encourage you to read the book On Talking Terms With Dogs - Calming Signals , by Turid Rugaas. It's a very easy read and will walk you through many of the very subtle signals that dogs use to appease another, defuse tension and avoid conflict as well as those distance-increasing signals that we are much better at picking up. Once you've learned what to look for, you may see a great deal of communication that you were unaware of before. It may be that the female is giving all sorts of appeasement signals that the neutered dog is ignoring and so she's forced to escalate to distance-increasing signals such as growling, snapping, etc. Or it may be that when she does growl, the neutered dog is responding with appeasement signals. Understanding the communication between your dogs will go a long way toward helping them learn to coexist.

You may also want to schedule an in-person consultation with a behaviorist or trainer who is familiar with dog-dog conflict. They should be well versed in canine communication (hopefully they've read the above book) and utilize positive reinforcement training methods to modify the behavior so that they can coexist peacefully. They may never be best of friends, but we can hopefully help them learn to just give each other space. Speak with your vet for a referral to a local behavior specialist or trainer.

You can also look on the APDT website (you should always ask questions of the person's methods and make sure you feel comfortable with their approach. Avoid people who utilize remote collars, choke or pinch collars, speak about 'pack leader' or alpha rolls, forced submissions or anything else of that nature.)


This link is for the American College of Veterinary Behavior (ACVB). Near the bottom of the page, there's a link to a PDF with information on how to select a trainer (that's also the name of the link). It walks you through training equipment and practices to AVOID.

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

Jody, APDT
Los Angeles Behaviorist

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.