Why Are My Dogs Suddenly Fighting?
What Predisposes Dogs to Fight?
This is one of the biggest problems affecting owners of multiple dogs and sadly one of the most difficult to manage. Two dogs generally getting along well as puppies may suddenly engage into vicious fights as they mature. A younger dog attacking an older dog may suddenly fight despite living in harmony for quite some time. Why is it that way? There are many causes for inter-dog aggression in multi-dog households and these are just a few.
If you own two female or two male dogs, fighting is not unusual at all. Some dog breeds are prone to being same-sex aggressive. For instance, Alaskan Malamutes, American Pit Bulls, and Boxers are breeds of dogs known for being same-sex aggressive. According to Nicholas Dodman and Alice Moon Fanelli in an article for Petplace, terriers may be prone to fighting because as a breed they have been developed to work independently.
However, any breed of dog, given the right circumstances and predisposition, may develop inter-dog aggression. Generally, these dogs got along well when they are puppies but once the reached social maturity (generally between 12 and 36 months) things dramatically changed and there is an explanation to this.
In nature, it would be quite unnatural for two females dogs or two male dogs close to the same age to live in the same social group. In nature, once the females and males mature, they would leave the pack to form their own group, or if they would remain in the group, they would respect the breeding right of the other female or male. According to Gail Fisher a dog trainer, breeder, with over 40 years of experience, "A pack with several adult males and females of the same age would rarely, if ever, be found in the wild."
This is further confirmed by the Merk Veterinary Manual:
"At social maturity, in free-ranging packs, dogs that challenge the established social hierarchy may leave and form their own groups if they do not succeed in altering the extant social order. This situation may be analogous to one form of inter-dog aggression that occurs in multiple-dog households. Social maturity is also the time during which problem aggressions and anxieties develop. In multi-dog groups, the highest-ranking animals may be the only ones to breed."
If the dogs are not spayed or neutered, there may at times also be a hormonal component to the fights. In female dogs, the hormonal changes taking place during the estrus cycle and pregnancy may particularly elicit fights. However, fighting may endure due to hierarchy and breeding rights even when the dog is not in heat or pregnant. Learn more about this in "Why Are Intact Females Fighting? In male dogs, the hormone testosterone facilitates inter-dog aggression, however, once spayed and neutered, dogs prone to inter-dog aggression may no longer fight due to hormones, but they may still viciously fight for other reasons we will see below.
Access to Resources
Social hierarchy is one of the main causes of inter-dog aggression in multi-dog households. According to dog trainer and owner of Peaceable Paw, Pat Miller, "Social hierarchies do exist in groups of domesticated dogs and hierarchy can be fluid". By nature, dogs are pretty good conflict solvers, indeed they are masters in ritualized aggression.
Ritualized aggression takes place when dogs resolve conflicts without biting. Growling, raising hackles, showing teeth, as dramatic as they are, ultimately help avoid actual confrontations. In nature, spending lots of energy fighting on minor issues is counter-productive as animals must save their energy on more important issues such as hunting and survival. T
So what causes actual fighting in multi-dog households to take place? Why are dogs biting and actually breaking skin if they are good conflict solvers? Let's take a closer look into hierarchy in dogs. According to Karen Overall, rank is contextually relative. A real high-ranking animal would be normally tolerant of lower-ranking members. The behavior of the lower ranking members towards the higher ranking member is what determines the social hierarchy. In other words, by "withdrawing", lower-ranking members make the hierarchical status clear.
Higher ranking members are those who regulate and maintain access to some resources, however, such access is contextual. A certain resource may be highly maintained at certain times when at other times it is not, or other resources may not be maintained at all. Resources, therefore, can be both contextual and subjective. What are some common resources from a dog's perspective? Following are some:
- Attention from the owner/guests (greeting the owner, interacting with the owner)
- Food (respect space when feeding dogs, or better, crate the individually for safety)
- Toys (especially the newer ones or toys that have not been around for some time)
- Sleeping areas (this could be a favorite bed, a higher spot or a favorite place)
- Bones (these are seen as high value even among dogs that get along, so practice caution)
- Space (many dogs have a space threshold, an invisible barrier that if surpassed may yield a dispute)
Generally, a high-ranking dog will maintain access to resource through a ritualized display, however, problems start when such displays are not effective. This is why we often see fights in dogs of similar or equal rank, the ritualized displays are ignored. At times, ignoring the display is not merely voluntary; it could be the lower-ranking dog ignores the display because it is over-ridden by an event that temporarily blurs the hierarchical status. We will see such circumstance below.
As mentioned, at times social boundaries can be blurred by events. For instance, if both dogs have not seen the owner for a long time, the lower ranking dog may not defer to the higher-ranking dog's right to access to the owner first because it cannot contain its excitement or it could be he feels the owner will protect him. When over excitement takes place, this is often a trigger for big fights to occur among multi-pack dogs. It is easy for the excitement to blur social rules causing a fight to ignite. At times, when dogs are playing, the high arousal levels may also elicit a fight.
Another example is territorial barking. When two dogs are highly aroused by a trigger seen behind a fence this may elicit a fight. The fight may be caused by re-directed aggression or simply because the higher ranking dog wants to be in control of the boundary (this explains why the higher-ranking dog may mark these areas repeatedly).
In re-directed aggression, the highly aroused dogs go into an hyper-vigilant state that triggers reactive responses which would not take place in a normal setting when the dogs are calm. Because of this possibility, it is always imperative dog owners of dogs who tend to fight to never physically get in the middle of two fighting dogs for the purpose of separating them. With high arousal levels, the dogs are in fight mode and anything between them could trigger a bite, which of course, is not delivered voluntarily. For more about this, visit the ASPCA's Virtual Pet Behaviorist for tips on breaking up a fight.
Changes in the Social Group
A typical scenario affecting social hierarchy takes place when a higher-ranking dog starts becoming weak or old. A younger dog that has reached social maturity may, therefore, ignore the ritualized displays of the older dog which will elicit a serious fight. At times, the senior dog may want to give up top position but is unable to defer in an effective way due to loss of sensory or motor abilities, and this may cause the eruption of serious fights. Because a dog pack in nature cannot be successfully led by a weak member, at times the fights may turn out quite blood and even fatal in some cases.
Another situation where pack changes take place is when a new dog is added to the social group. In such a scenario, the dogs will require some adjustments. Often, fights may ensue, but they can be temporarily until an agreement is found. The way the owner handles the situation may exacerbate the situation. Giving too much attention to the new dog may only create more conflicts. At times, when a dog has been away for some time and is then re-introduced to the pack then there may be some problems as the pack order may need to be re-established.
At other times, dog owners may further exacerbate pack dynamics by intervening. Often, the owners do not have any idea they are creating problems by defending a lower-ranking dog. By protecting a lower-ranking dog and correcting a higher-ranking one, the owner escalates the problem. Dog behavior expert and obedience trainer, Stan Rawlinson, also known as the ''Dog Listener'' suggests dog owners to not fuel the fire by feeling bad and ''rushing to protect the would-be subordinate from being "bullied".
This can cause problems and potential fights. Nicholas Dodman calls this form of aggression "alliance aggression" and states it typically occurs when the owner interferes with the establishment of a stable hierarchy.
Poor Social Skills
Not all dogs are blessed with great social skills. If a dog has been poorly socialized, there are chances it may not readily recognize normal social behaviors. These are dogs that feel compelled to attack other dogs for simple things such as panting, wagging their tails or sniffing under tails. These dogs are socially illiterate and must learn the ABC's of normal social language.
While some dogs may have been socialized with dogs as puppies, they often forget the language if their inter-dog socialization ends at some point. However, some breeds by nature are not social butterflies, and this must be respected. They may never be happily romping at dog parks but at least they should be able to tolerate walking by dogs without acting aggressively.
What About Dog/Human Interactions?
While a social hierarchy is seen in multi-dog households, it is important to point out that humans are not dogs, and therefore, it is pointless to assume the "alpha role" to earn respect. The dominance myth has been debunked, and the latest studies suggest that dogs are for the most part not status-seeking entities attempting to rule the home, but simply opportunists that will do whatever behaviors are reinforcing to them.
Why Call the Pros
As seen, dog fights are serious issues that can be exacerbated if the owner does not intervene in the correct way. Trying to make the dogs "sort things out" is not recommended. There are countless owners who attempt to "step aside" only to report weeks later their dogs got into a dangerous fight that cost hundreds of dollars of vet bills for stitches.
If your dogs are fighting, call a professional, that is a reputable dog trainer well versed in dealing with dog behavioral problems, a veterinary behaviorist or a certified applied animal behaviorist.
Disclaimer: if your dogs are not getting along, make management your top priority and consult with a reputable professional. This article is not to be used as a substitute for professional advice as only a professional can give advice upon assessing and evaluating your dogs in first person. By reading this article you automatically accept this disclaimer.
For Further Reading
- Medical Causes of Aggressive Behaviors in Dogs
medical causes of aggression in dogs, It is an unfortunate fact that often dog owners feel compelled to give up on their canine friend as soon as he displays aggressive behaviors by either giving him away, or...
- Dog Behavior: Considerations for Re-homing Aggressive Dogs
Learn why re-homing an aggressive dog can be downright wrong. So what to do with an aggressive dog? There are some options, but there is little left to do with dogs with a bite history.
- The Risks of Raising Two Female Dogs
Learn why female dogs may not get along as wished. Same sex aggression is common in dogs and at times, the fights between two females may get fierce. Learn why good leadership is important.
What do your dog when your dogs fight?
This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.
Questions & Answers
My dogs get along 95% of the time, and then all of a sudden out of the blue, they start fighting and don't get along. It seems to last a week or so then they will go back to getting along. I have no idea what causes it. What can I do to get them to get along again?
It would be important finding out what triggers the behavior Although it might not seem like there is a trigger, most likely there is one and work needs to be done based on that. You would need the intervention of a behavior professional for an evaluation and behavior modification.Helpful 55
My dogs fight and we stop them, but then one or the other starts it up again. It is getting too hard for me. What can I do?
You have several options: You can keep them separated all of the time, rehoming one or consulting with a behavior professional. It would be important providing the professional with details on what seems to trigger the fights, in what context they occur and whether there is any history of injuries. The professional can then assess the situations and provide suggestions on what course of action is needed. This is important at a safety level as well considering that, when stopping dogs who are fighting, there are always risks for a redirected bite.Helpful 18
Two of my dogs have been best friends for five years. In the last four months they have had a few fights which are the likes I have never seen. They have literally tried killing each other. And a bit like you said above on the last two occasions the smaller dog has been to the vets twice where my other dog has cut her badly. I have phoned a couple of professionals but am yet to see one as they are busy at the moment. Is there anything I can do in the meantime that would help?
Yes, management is your best friend as you wait to see a professional. Basically, keep the dog separated. This may mean in crates or in separate areas of the home where they can't reach each other. Baby gates may be another option. You may need some sturdy ones and put some mesh wire between the gaps to prevent access to each other.Helpful 29
I have a male and a female dog. They are just two-years-old and are also brother and sister. They have suddenly started fighting. What can I do to rectify the situation?
Dogs can fight for many reasons. Often, they are erupted by some form of resource guarding or access to a resource. It is important determining if these are actual fights or just noisy "discussions" or if they are actually real fights. At this age, both dogs have reached social maturity and disputes are not uncommon. You may need to consult with a dog professional on this one, especially if the fights are real and not just ritualized aggression and there is a risk for tension among the dogs and potential injury.Helpful 15
After a recent loss, which resulted in leaving behind a lonely 6-year- old greyhound, we decided to introduce her to another dog. For the past couple of weeks, they have been playing and have been fine with each other. However, there were two instances when they didn't get along. Why could have caused this?
There can be many possibilities. It is important to analyze in what context this happened. Was it around toys, food, bones, or a sleeping area? Was one dog resource guarding you? Was it through a doorway or a small space? Did one dog insist on playing while the other wasn't willing? Most of all, was it just a noisy squabble that ended there and nobody got injured? Many dogs living together have small "discussions" which are just part of communication, but you need to keep an eye on these interactions in case they escalate to something more. If both dogs were engaged and there seemed to be a real intent to harm each other, in such a case, it would be best to have a professional evaluate the situation.Helpful 15
© 2012 Adrienne Janet Farricelli