Guide To Australian Shepherd Training & Care
Guide To Australian Shepherd Training and Care

My Aussie Is Suddenly Dog Aggressive...

by Kym
(Colorado Springs)



I have owned Aussies my whole life. I have my 5th one now, a 2 1/2 year old female. She is the sweetest thing ever or at least she was. Suddenly, she is attacking my other dog for no apparent reason! I have 2 other dogs (a 3 year old Border Collie/Aussie, and an 18 month old German Shepherd) and 1 foster (a 1 year old Boxer mix). I am VERY careful about 'integrating' fosters into my 'pack' (I have been fostering for years-no problems.) They were all living peacefully for the last week and then it happened... my Aussie attacked my German Shepherd out of the blue and my Border Collie joined in (a pack thing?)

I thought everything was ok (thinking back hind-sight, thought it was over 'fast food' YUMMY)so... no more food around the dogs. Two days later, everyone is out playing together ( I am with them) and all of a sudden... she attacked my Shepherd AGAIN! And then they all jumped on her!! I was alone scared to death but managed to get them off of her with minimal damage...

WHAT IS HAPPENING TO MY SWEET DOG???? PLEASE HELP ME HELP MY DOG!!! I don't want to get rid of her but I cannot have this behaviour. They all get LOTS of exercise, go to the dog park, well socialized...

Comments for My Aussie Is Suddenly Dog Aggressive...

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My Aussie Is Suddenly Dog Aggressive...
by: Anonymous

That's interesting as my 20 month neutered Aussie male has recently started being snappy - mostly with German Shepherd males too. He doesn't look for trouble but if they get in his face he let's them know in no uncertain terms that he wants them to back off.

Re:Your comment
by: Kym

Thanks for that interesting fact. My last aussie male was dog aggressive but only towards Rotties and Chows (I adopted him at 8 months) I thought maybe it was an issue from his past..My current aussie I have had from 8 weeks, no 'bad' past (attacks,etc) My shepherd is VERY passive(and spayed) so she shouldn't be threat right?
She has gotten better the last few weeks but not without LOTS of obedience(back to basics) and LOTS MORE excersise(like til she's exausted!)
I still don't trust her,and keep her in my sights,on a leash in her kennel at ALL times. She isn't allowed any freedom without my say so..
and I don't allow her with the other dogs unless there is someone else here with me.
I wish you the best with your dog..Good luck.

dog aggression in aussies
by: alicia

HI Kim, I have a 16 month old female also blue merle. I have been taking her for obedience training and agility since 7months old. I have also taken her to dog parks, she has displayed aggression but also saw improvement depending on certain dogs that were there. Anyway, she also acts aggressive esp. when on leash. This past fall my husband and I would take all our dogs for a 1 hour hike and meet dogs along the way. I saw improvement when we stopped she would greet in a nice way without lunging or growling. Other than this she is a fantastic dog and very smart and funny! Hoping I can find a way to stop this esp. for agility. There is a you tube teaching on what they call counter conditioning. It looks like it works too!

dog aggression
by: Anonymous

Kujo is ball mad, and loves nothing better than flyball and is very focused when he thinks there is a game on hand.The way I am handling this at the moment is that when I see another dog approaching that might be an issue I show my boy the ball and he completely ignores the other dog. He only goes back on the lead if he looks like getting involved and that has happened for a while now.

Re: Suggestions
by: kym

Thank you all very much for your suggestions and your own stories. I am willing to try ANYTHING for her to be a well rounded dog. If nothing else it's nice to know there are people out there willing to help and not criticize!! Thank you to all! And we will keep working!

unusual aggression
by: Marg

Hi! My own Aussie, always friendly with every dog she met (she is 5 years old) has recently started attacking small dogs and been much quicker to initiate a "rumble" with other dogs. I called her trainer who suggested I get her thyroid checked out. Apparently if a dog is hypothyroid it can cause sudden aggression. As I already treat my girl for low thyroid, this is probably not the reason for her behavior, but you may want to look into this or at least read the literature on it.
Good luck!

My assie is dog aggressive.
by: Del

Hi Kim,My Aussie is 2yrs old now and she has been aggressive since she was a pup around 4 to 5 mths old.She was realy bad then,she would would see another dog from a fare distance and she would pull me trying to get to the dog.
As she got older she got much better,I can just about walk passed a dog before she attacks but it is not all the time.I do obediance with her and she is good if she is focused on me,but if another dog gets too exicted that wiil send her off.I would be happy to be able to have her relaxed next to another dog.I think it is a matter of letting them know your in control,which is something I'am still learning to do.So good luck to you and staying calm I found works well..

Re: Aggression
by: Kym

Thank you everyone for your help! I really appreciate it!With everyone's help she is getting better. I still don't trust her, but she is improving!

Daughters visiting aussie attacked my small dogs
by: Anonymous

My daughter left her aussie with us for about 2 weeks. I have 4 female old golden,an old female chiwawa,an 8 year old small male mix(not sure what)and female chiwawa mix. All my dogs are 8 plus years and set in their ways. My daughter's dog (named Dunngy) is only 71/2 months old. Her dog out of the blue attached my old female chiwawa by the hip and tossed her. growling and ready to hurt her more but We intervened. We disciplined Dunngy and he seemed depressed and remorseful but later the same evening he again attacked my little male dog by the throat and wouldn't let go...all the while we're yelling and pulling him off. Three days later in the backyard after a nice long walk and swim he again attacked my little male dog.This time there's blood and no reason for this behavior. We immediately had Dunngy nurtured and made arrangements for him to be picked up with my daughter. My I trust that this is now an ingrained behavior and should I not have him visit again or do I hide my dogs away from him if he's ever over again?

Australian vs. German & then Aussie vs. World!
by: Anonymous

So I accidentally stumbled across this page & found your story very similar...I adopted an Australian Shepherd about 1.5 years ago now, who was a foster at the dog daycare I work at. I happen to have a German Shepherd who I rescued as a pup pup. I fostered my Aussie for about 3 weeks to see if she'd fit in the pack, and all was well. My German was 3 at the time & the Aussie about 2 we think. Yes they have had their sibling fights, 4 to be exact, the were nasty, I got hurt more then them....but they both saw red...usually a jealousy thing, not putting blame on one or the other, it always happened so fast...I know why my G. Shep "sees red" when someone goes after her, because she was attacked a few times as a young dog, she's anxious & fearful now...but my Aussie brings it, yes it's true, the alpha dog! She plays great with other dogs, the rougher the better, BUT...if in anyway she feels dominated she'll try to bite and growl and pin the other dog down. With the exception of fighting her sister/best friend she has never actually done any looks and sounds scary, but that's not her "red" cuz I can call her off easy. Long story short... The breed does have a stubborn spell...breed for taking control. But most of your comments weren't a "breed" issue nor a "breed on breed" issue, they were all about who was really in control! The "pack leader" It sounds like in all our houses our Aussie's are the pack leader, whether we want to admit it or not!

Despriate for Help
by: Anonymous

I have a 17 month old male who is still intact he became very dog aggressive when he was attacked by another dog now I cannot trust him or have him around other dogs I need help how do I break him of this. I cannot take him to dog park I do not trust him with strange dogs in fear he will attack. Today he jumped out of the back of my truck when another dog was chasing us down the street.

Newly Aggressive Aussie
by: Anonymous

Hi - I'm not sure how old this post is, but recently my 10 1/2 Aussie is becoming aggressive towards our other dog (a 5 yr old American Eskimo). They've been living together for 2 yrs after I took her in from my parents, but have known each other since my Eskie was 6 months. They've always gotten along great, to the point that the dog trainer we had come to our house a couple of months after we had taken in the Aussie to train them together (for walking and barking purposes) said she couldn't believe how dependent they were on each other and how they had formed such a strong pack together.

Over the last couple of years we have learned a few things, like she would become toy aggressive, but we bought each dog their own toys (different in styles) and trained them to not touch each others toys, which completely stopped that negative behavior. We also have two completely different dog bowls in different spots in the kitchen for feeding and make each dog sit in front of their feeding spots before putting their bowls down and until today there really hasn't been a big issue. However, today my Aussie started to growl next to my other dog as he was eating his food and before I could get there she was attacking him! I've noticed in the last couple of weeks that she's been hovering around his dish, but didn't think anything of it until now, but I guess hindsight is 20/20!

I guess my question is after this long post, has anyone else seen this start to happen in their Aussie? And/or does anyone have any recommendations? I have to leave for work in a couple of hours and am thinking of separating them for the first time since they've been together because I feel a little nervous leaving them alone.

Aussie Aggression
by: twilightaholic

My 2 1/2 year old aussie is loveable as he'll but will snap without reason or over react and attack our 9 year-old mini schnuazer. We also had an issue with snapping at a young child when she ran toward the puppy. Any assistance would be great! My husband did not see him and stepped on him got bit but not hard to draw blood then went after the schnuazer just for being there.

by: Kathy

I have a Austrialian sheperd mix, also have a beagle and a lab. The beagle and the Austrailian sheperd can't get along. if I'm not home with them. Their totally different but when I come home that's when they start. There jealous of me neither one will let the other get close to me or they fight.. Any suggestions I have considered getting rid of the Aussie he just turned a year and none. Of them are fixed..... Thanks

Aggressive Aussie
by: Candace

Just read others posts on aggressive aussie's.
We have a 1yr old Aussie and a 7yr old German Shep. The two boys got along grand, until recently, this week,our Aussie, Frodo, picked a fight with our German Shep. Samson. It was very scary. had all I could do to pull them off each other. Sam has puncture wounds on his leg. Later in the week, Frodo did again with my neighbor's Aussie, who is Frodo's litter brother. It was all out war between the two. I tried to break it up. I got bit in the process. Both dogs are ok. but it was traumatizing for me and my daughter. I've enrolled Frodo in Obedience right away to curb this behavior and to learn how to deal with this behavior.

Sound just like my blue merle...
by: Anonymous

I have a 3 year old blue merle that fits the mold of the discussion thread. She is the sweetest dog with people, but with other dogs she seems to always need to prove she's dominant. I used to be able to take her to Pet Smart with few problems, now she growls at some dogs and others she will start out OK, but if they are over-active she immediately begins trying to "herd" them with staring/growling/batting with her paws. She is worse with the big dogs like german shepherds and huskies. Walks around the neighborhood are impossible if we cross another dog. I have tried training with a pinch collar/holding her close to the side but it doesn't seem to impact her behavior. We lover her to death but she seems to be very dominant and very stubborn.

Aggression in Aussies
by: Anonymous

My mother in law's two Aussies, altered male and female approximately 3 to 4 years old, suddenly attacked and killed my 14 year old otherwise healthy German Shepherd a few days ago after living peacefully with her for 3-4 years. It was sudden, viscious, gruesome, and very unexpected. I found out afterwards that general signs of aggression were exhibited earlier but easily corrected. The attack happened very early in the morning while the household was asleep.

Killer Agression
by: Anonymous

A few days ago my mother in law's 3-4 yr old altered male and spayed female Blue Merle Aussies who had been living with my 14 year old Gentle Spayed German Shepherd peacefully for 3-4 years visciously attacked my German Shepherd. The wounds were so severe my dog died. There were no wounds on the Aussies. They had shown signs of aggression on the ranch but the aggression was quickly subdued by their humans. The attack occurred very early in the morning in the dog's large enclosure.

Suddenly aggressive
by: Candace

I have learned with my 1 1/2 yr old male aussie, who was aggressive with my sweet passive G shep. and my neighbor's aussie, i wear them out, play and exercise like you are doing. always supervise. I crate both my boys overnight and when we are not home, this keeps them out of trouble.
Our trainer for our aussie told us to have a water bottle handy to squirt them if they get into a fight with another dog, which was a huge fear of mine. But never try to break it up yourself. I got bit trying to do just that. So crate them when they can't be supervised, separate food areas, wear them out, the pinch collar worked very well on our aussie, gets his attention immediately walking.
Someone on this thread said the aussie has to be the pack leader, I think I agree. Ours is doing well, no incidents since last July. Always on guard though. Our trainer also mentioned the be sure the dog is well fed and has enough to eat, hunger can lead to aggressiveness. So feed your dog enough so he's comfortable, he'll burn it off with his high energy.
Hopefully we can all help each other! Thanks!

My Aussie Is Now Aggressive to Other Dogs
by: Cathy

Wow, I can see that many of you are having the same problems that I am with my Aussie boy. He was 2 in July. Got him from the breeder at 4 months of age and took him to obedience class where he was socialized with other dogs. Started him into agility class and he was friendly with all the other dogs but had to watch him as he would play to rough with the little ones. Just a couple of months ago he snapped at a puppy at class and today he attacked my little Papillon (he is okay, pulled my Aussie off him immediately). This is so depressing as I was hoping to do so much with him, the agility and such. Now I feel on guard all the time at class. He was neutered at 4 1/2 months of age. I just can't understand it as I did socialize him as a pup.

Newly Aggressive Aussie - part 2
by: Anonymous

I wrote my original post a few years ago about my then 10 1/2 year old Aussie becoming aggressive. After she had randomly attacked our other dog we watched her more closely for a few days and noticed she seemed to be nursing one of her legs. She'd been fine again with our other dog, so no worries there, but we took her to the vet just to make sure everything was ok. They took X-rays of her front leg and we found out that she had pretty well developed arthritis and that she was probably in quite a bit of pain. Our vet explained that she probably attacked our other dog because of that, feeling that he was invading her space while in pain, and that it had nothing to do with the food. We put her on pain medication supplemented with glucosamine tablets and the aggression issues completely stopped. She passed away last spring, (March 2015), and only had one other aggressive episode after about two years of being on the pain meds and all we had to do was up the medication dosage. Until she passed away, she was completely fine with the pain meds everyday. They helped so much(!!) and changed her quality of life for the better.

In short, for those with older dogs who've become aggressive after never having been before, talk to your vet. Our issues revolved around the pain we didn't know she was in.

I love love my Aussies BUT.......
by: Anonymous

Wow! Reading these comments would discourage many people from having an Aussie! We have had Aussie dogs for the past 32 years. 2 mixes and 6 pure. Right now we have a 6 yr. female blue fixed and 1 male blue 20 months and 1 male red 2 yrs both not fixed. In the past 4-5 months they are best friends and out of no where they fight like crazy. It terrifies me! It started with food now eat separately. Competitive galore. Both sweet. I cant believe my eyes. Out of my league. Cant trust them at all. Our sons tell me to relax and I'm over reacting. My husband is sick of it but not to the degree I am. I am the major care giver and scared.

Possible SSA
by: Anonymous

In any household with young males I would be concerned about same sex aggression (SSA), particularly with a female thrown in the mix and the males intact. Dogs do not mature sexually and socially until they are 18-24 months old, sometimes older. This can give an owner the impression that they have no problems with their dogs because the dog is not socially matured and has not challenged any other members of the family (human or otherwise). When there is a problem, it seems to be out of the blue. Many larger and working breed dogs are highly prone to same sex aggression, and males are also more prone. Neutering does not generally address the issue. I would contact a behaviorist and keep them separated until you locate the source of the issue.

My Aussie is Suddenly Dog Aggressive
by: Cathy

I have a neutered blue merle Aussie. He was socialized as a pup, taken to obedience and agility classes and still takes agility classes. Upon the age of 2 he suddenly became dog aggressive. He doesn't aggressively attack, but if they get in his space he does not like it. He does want to go after little fluffy type dogs though. One day he went to attack my little male Papillon when the Papillon got close to his crate. So now he cannot be around any of my small dogs. I love him dearly but know that I must be on guard at agility class and in the future when we go to trials. Unfortunately many people will let their dogs run up to him. They always say "My dog is friendly" but that's not the point. Keep your dog out of my dogs space PLEASE! Things would be a lot less stressful if people would do that. It's kind of lonely keeping off to ourselves when other people can sit together and not be afraid of their dogs mingling. But I would not trade him for the world.

Aussie attacking my small dogs
by: Anonymous

I have a 1 yr old not fixed female Aussie. When she was just only about 5 months old she started to attack my Maltese and Yorkie. Only when I came home and they all would greet me. So I was prepared for it upon entering the house and sprayed her with vinegar water and threw my keys down anything to distract her. It worked the first few times only. Now she is attacking them just randomly and I have to pull her off before she kills them. I love all my dogs and can't imagine rehoming any of them. I don't know if Aussie can be broke of this. I am thinking of taking turns crating them. I will do what ever to ensure my little guys don't get hurt maybe I will have to consider rehoming them. I will never part with my Aussie. She does have some issues but Aussies are my always and forever breed.

Stay with it - Aussies are smart and will learn better behaviour but you have to show who's in charge so they can back down from fights
by: Jemma

My intact 3 yr old male, barney, was well socialised and friendly with all other dogs. He would bark at humans coming to house or running etc but he quickly got trained out of that. He went to dog training and did well. From 14 months he changed and when threatened by other dogs he would attack back. It was very stressful for months and it seemed 50% of walks down by the canal near us ended in fights. I took him to the vet to discuss neutering. She said it wouldn't necessarily stop him being attacked but might change his personality and he would become a frightened dog and prone to being aggressive himself. She suggested going back to basics with training and learning to read the signals better. I stopped walking him by the canal as enclosed spaces are not great. He now goes for hours every day on a common with lots of dogs. He avoids any conflict and we are all much happier the last 6 months. He's turned a corner. I have to be vigilant but it's so much better.

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