I’m writing to you tonight because of my 11-month-old girl's behaviour, as she’s becoming increasingly aggressive towards other dogs... This evening, she actually bit and injured another dog that hadn't done anything to her at all.
She’s been acting aggressively for a month or two now, and I just don’t understand it. She’s always been used to seeing other dogs, being off-lead, and playing with them. Over the last two months, as soon as a dog she doesn’t know approaches her, she growls, gets snappy, or even attacks, even if they’re just coming over to say hello. I initially thought it was because she was in season, which started right around that time, but now that it's over her behaviour hasn't changed, so I’m at a loss... She hasn’t been attacked by another dog, there’s no trauma or bad history that I’m aware of, and she’s always been well-socialised with other dogs, getting two hours of walks a day... I really don’t get why she’s suddenly become so aggressive and I feel a bit helpless. I’m also not sure how I should be reacting to make her understand that it’s not acceptable to go as far as hurting another dog...
Does anyone have any clues or similar stories? Any potential solutions you could suggest?
Thanks in advance for reading and for your help.
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Hi there, it’s also quite normal to see changes in a dog as they mature. Seeing as a dog goes from being a puppy to an adult so quickly, their behaviour can often change. Our girl, who used to love other female dogs when she was younger, now really struggles with other dominant females.
The key isn't to force them to play together, but just to get them to "tolerate" each other. To achieve this, getting help from a dog trainer is often the best way forward.
Evening! Basically, if you think she’s attacking to protect you, you could start by having her spend a few days somewhere where there are other dogs. If she’s a bit wary of dogs she doesn't know, start with a dog she’s already familiar with.
If she’s possessive, avoid doing the opposite; even if it’s a dog she knows, don’t bring another dog into your home as things could easily turn nasty with any dog on her own turf.
One final point: don’t forget that dogs still have that wild instinct at the back of their minds, so it’s not impossible that she’s acting this way because she’s a dominant female.
If she is dominant, she’ll need to learn some self-control, and you should ideally choose non-dominant dogs for her to socialise with.
Hi there,
I’m going through exactly the same thing as you... ever since my girl came into her first season, the relationship between my 5-year-old male and her (7 months old) has become very tense. They’ve fought on several occasions; there were no wounds, but it’s very scary to watch. We’ve had to separate them while we try to sort things out, so he’s currently staying with my parents.
I’ve also noticed she’s starting to show aggressive behaviour towards other dogs, which she never did before, and even towards people (barking and growling), which is also a first for her...
Did you notice a difference after having her spayed?
I must admit I’m at my wits' end... and leaving my dog at my parents' house long-term just isn't going to be sustainable for me.
Thanks for your help.
Hi there, if your dog has reached the point of being aggressive towards other dogs, you should definitely see a dog behaviourist to get this sorted as soon as possible before it gets any worse!
We can give you a few tips here on the forum, but we won't be able to fix the issue entirely.
You'll need to look at what 'calming signals' your dog is giving off before they go on the attack. Dogs communicate a huge amount with each other that we often miss (like lying down, licking their chops, walking in an arc, or squinting...). It’s important to figure out if your dog is communicating first or going straight to growling and lunging, so you can find the root cause of the problem.
Obviously, don't tell your dog off when they're being aggressive; they won't understand it the way we do (i.e., that they need to stop the behaviour). In fact, scolding them will just make them associate meeting other dogs with something even more negative, which won't fix things and might even make it worse.
Don't let this stop you from taking your dog out for walks or make you avoid every dog you see, as that will only reinforce their aggression. I'd suggest using a long training lead (at least 5m long) for now. When they meet another dog, let them communicate freely by keeping the lead as slack as possible. If you see them baring their teeth or curling their lips, end the interaction and walk away.
Try to stick to interactions with dogs that are off-lead. A dog on a lead can’t express themselves properly because their movement is restricted, which can lead to misunderstandings and aggression. The same goes for your dog—don't keep them on a short lead when they meet others, as they won't be able to communicate well and might be more likely to lunge. Also, having tension on the lead when they meet another dog signals to them that the situation is negative, so try to avoid that.
The tips I’ve given you here will help manage the aggression but won't get rid of it entirely. You really need to see a dog behaviourist (one who uses positive reinforcement) to help you find the root of the problem.
Evening Djenga, first of all, thanks so much for taking the time to reply! Ever since she was born, my little Calie has been a total sweetheart with everyone, humans and other dogs alike! I’ve socialised her with other dogs from a young age (training classes, friends' dogs, etc.). She’s always been very playful with them. I’m lucky enough to live in the countryside and get on really well with my neighbour who has a 5-year-old female Cocker Spaniel; for a long time now, we’ve agreed to let the two dogs stay together at my place during the day so they don’t get lonely! There’s never been an issue and even now, there’s nothing to report! My parents have a male Westie... and my little Calie still plays with him even now! I’ve got a cat and the neighbours do too, and no problems there either! BUT since the end of her first season, her behaviour on walks has changed towards dogs she passes.... and just like you, if I stop, it makes things worse!!!! It feels to me like she’s protecting me or being very possessive! If the outburst passes and contact is actually made, she’s fine (but I have to admit I’m a bit nervous now and I hardly ever let it happen anymore!) The behaviourist has suggested for the time being that I should distract her with some ham or raw meat when we pass another dog so she’s more interested in the food than the dog.... just so she doesn't associate other dogs with a negative encounter, and especially not to shout at her or be rough! I’m getting her spayed in two weeks (a decision I’d already made a while ago because I’m often in the woods with her and she runs around like a mad thing off-lead :-) PS: it’s a spot where there aren’t any other dogs!) I don’t know if she’d actually go and attack another dog if she was off-lead, I don’t dare try it.... I’m going to keep doing "moving" meet-ups with other dogs so it isn’t seen as a negative encounter, and I’ve started walking her in town again (I hate it) just so she sees something other than our lovely forest :-) PS: Calie is an Australian Shepherd cross Munsterlander, so she’s got plenty of energy!
Hello, did the spaying calm her down? Ever since her first season, my ***** has been aggressive towards my first dog, which keeps starting fights... ever since she’s been done and had an outburst (after her first season), she’s been like this... as soon as there are cuddles or food involved... it’s making me sick with worry because rehoming either of them is just unthinkable... thank you for any replies, please no judgement or negativity... (we rescued her as a puppy because the previous person was going to dump her on the street...)
Hi Djenga,
First of all, thanks so much for taking the time to get back to me!
My little Calie has been a total sweetheart with everyone—both humans and other dogs—since she was born! I’ve made sure she’s been around other dogs from a young age (training classes, friends' dogs, etc.). She’s always been very playful with them.
I’m lucky enough to live in the countryside and get on really well with my neighbour who has a five-year-old female Cocker Spaniel. For a long time now, we’ve agreed to leave the two dogs together at my place during the day so they don’t get lonely! There’s never been an issue, and even now, there’s nothing to report!
My parents have a male Westie... and my little Calie still plays with him even now! I have a cat and the neighbours do too, and there are no problems there either!
BUT since she finished her first season, her behaviour on walks has changed towards the dogs she passes... but just like you, if I stop, it makes things worse!!!! The impression I get is that she’s protecting me or being very possessive! If the outburst passes and we manage to make contact, she’s fine (but I have to admit I’m a bit nervous now, so I hardly ever let that happen anymore!)
The behaviourist suggested that for now, I should try to distract her with some ham or raw meat when we pass another dog so she’s more focused on the food than the dog... the idea is that she doesn’t associate other dogs with a negative encounter, and above all, I shouldn't shout or be rough with her!
In two weeks, I’m having her spayed (a choice I made a while ago because I’m often in the woods with her and she runs around off-lead like a maniac :-) ps: that's in an area where there are no other dogs!)
I don’t know if she’d actually go and attack another dog if she was off-lead, but I don’t dare try...
I’m going to keep meeting other dogs, but like you, I’ll keep moving so it’s not seen as a negative encounter, and I’ve started doing city walks again (I’m not a fan) just so she sees something other than our lovely forest :-)
PS: Calie is an Aussie cross Munsterlander, so there’s plenty of energy there! :-)
Hi Djenga, I’m having exactly the same issue with my 11-month-old girl! Have things improved at all since your post? If so, how? Thanks in advance – I have to admit I’m feeling a bit at a loss :-( She’s such a little sweetheart otherwise!
You should tell us a bit more about your pooch so we’ve got more to go on! What was she like before, and what’s she like now? When did this all start? Has anything unusual happened in her environment or while out on a walk? Have you had a chat with your vet about it, or maybe anyone else who knows your girl?
Hi Galass,
A lot has changed for us over the last year. We explored a few different avenues before finding solutions to make the situation more manageable. First, we spoke to her vet. He’s been seeing her since she was a puppy and knows her well. After checking her over and doing a general check-up to see if it was a health issue, he suggested that the hormones from her first season might be a factor. But as I said, she stayed aggressive for a good while after her season, which made me think that wasn't the cause. I then contacted a behaviourist who just told me it was her "natural temperament"—an explanation I didn't agree with at all.
In the meantime, my girl kept being aggressive towards other dogs, and I ended up getting really anxious at the thought of running into any dog while out on a walk. I’ll admit I didn't have the best reaction at the time; I simply stopped going anywhere near other dogs. That lasted for about a month or two. Then, I went to stay with my parents, who also have a dog. At first, she was very aggressive and defensive. But after 24 hours together, she FINALLY relaxed and played with him like a puppy. We stayed for a few days, and I think she relearned her doggy social cues. I reckon that was the moment it clicked for her.
From that point on, she’s been much calmer around other pups. I’m not saying her aggressive behaviour has gone completely—far from it—she can still be very defensive at times, but that’s when I step in. If I see her starting to get aggressive, I keep moving and ask her to follow me. I’ve noticed that when I stay static and don't move from one spot, that’s when things can escalate. So, it’s a tactic to get her to adopt a different behaviour. Usually, if the other owner is okay with it, I ask if we can walk together; she doesn’t show that behaviour at all then, she’s more likely to follow the other dog or just potter about rather than being aggressive.
She can be a bit picky about who she likes, but she’s starting to play with other dogs again, which is a huge relief. I’ve also noticed it’s mainly towards other females that she acts this way, which has made me reconsider the hormone side of things. She’s also at her least pleasant towards others when she’s in season. So, I try to adapt and see how she reacts to other dogs. During those times, I prioritise walks with dogs she already knows and likes, and I’m extra cautious with dogs we don’t know.
