Funny Dogs reaction in public when watch other dogs

Why would my dog fight with dogs he has never met?

Generally, most well socialized dogs strive to avoid physical or aggressive confrontation. Dogs use body language to communicate desire to interact or desire to avoid an aggressive encounter. Like people, not all dogs are natural or skilled communicators with members their own species.

"The diagnosis is based on the body postures and reaction of the dog when faced with another dog."
Aggression between unfamiliar dogs can be due to fear, poor communication, defensive, possessive behavior over resources (including perhaps family members or other pets) or territorial behavior over territory or owner. Aggression between dogs can result in injury to dogs and/or to the people trying to separate them. The behavior can consist of growling, snarling, barking, lunging, snapping, and biting (see Canine Communication – Interpreting Dog Language).

How do I recognize fear-based or defensive aggression toward unfamiliar dogs?
This aggression is very common in aggressive encounters with other dogs.

This aggression is very common in aggressive encounters with other dogs.

The diagnosis is based on the body postures and reaction of the dog when faced with another dog. However, these postures and reactions may change over time depending on the consequences of the interaction. For example, if the dog learns that the aggressive display stops encounters, the behavior tends to increase in intensity and the body postures may become more confident. Therefore, it is important not only to observe the expressions and posturing at the present time, but also those from the initial few encounters. The fearful dog will often have the tail tucked, ears back and may lean against the owner or attempt to get behind them. They may be barking at the approaching dog, while lunging and backing up at the same time. Often the dog is avoiding eye contact. This behavior may begin due to previous aggressive attacks from which the dog could not escape and sustained injury. Some dogs who have had limited or insufficient early socialization with other dogs, may lack the social skills required to interact playfully and comfortably. When multiple dogs are present, if one dog is highly aroused and unable to be calmed or controlled by the owners this dog may incite the second dog to become fearful or defensive, which ultimately leads to aggressive displays from both dogs.

Often the owner plays a role in how the dog behaves. For example, the owner may signal tension via leash tightening responses or even “corrections” that signal the dog that the approaching dog or at least the situation is of concern. In addition, if the owner is frustrated, anxious or worried about the dog’s behavior, then the dog is likely to notice the owner’s reactions and associate them with the approach of the other dog (rather than their own behaviors). This may result in a dog becoming even more defensive and aggressive. An owner that tries to calm their aggressive dog may serve to reinforce the actions the dog is engaging in at the time. Conversely, if the owner threatens or punishes the dog in an attempt to stop the behavior, this will only serve to heighten the dog’s fear and anxiety in relationship to the stimulus. Good control can help to calm the dog; owners who have their dogs restrained on a leash (especially with a choke or pinch collar) and have poor control often will have highly defensive dogs. Dogs that are restrained on a leash or tied up The diagnosis is based on the bodypostures and reaction of the dog when faced with another dog.
are more likely to display aggression when frightened, because they cannot escape.

How do I recognize aggression resulting from poor communication between unfamiliar dogs?

This aggression can be elicited by assertive gestures or postures from either dog. These can include placing head or feet on the back of the otherdog or other dominant body postures such as eye contact, and high tail and stiff-legged approach. If one of the two dogs does not show appropriate appeasing or submissive responses toward the other dog, then aggression might ensue. Owners may inadvertently heighten the anxiety and arousal by how they respond; pulling and tightening or correction with the leash or when they use threats or disciplinary techniques. These may signal to the dog that the impending approach is problematic. Leash restriction also does not allow the dog to react with a complete rate and range of responses, including body postures, approach and withdrawal.
Some dogs may be uncertain how to communicate properly with other dogs. This may occur because of insufficient or inadequate socialization with other dogs or dogs of different types and breeds, or because of previous unpleasant experiences with other dogs, adding fear or anxiety components to the problem. Problems may escalate quickly in dogs that are anxious or fearful, and in dogs that lack good social skills with other dogs. For example, if assertive or dominant expressions and gestures, or highly excitable and overreactive displays frighten the other dog, aggression by one or both dogs may occur. Conversely, the signaling dog may not be reading the signals of the second dog and might increase the intensity of its displays, perhaps to the point of aggression, even when the other dog shows deferential behavior. This can lead to the second dog becoming defensively aggressive. Good communication within a social group of familiar dogs will result in a minimum of fighting, through actions, posturing, and visual and vocal signals, this does not necessarily work when unfamiliar dogs are meeting and greeting for the first time. In addition, changing circumstances and environments on walks, behavioral genetics, lack of sufficient socialization to other dogs, previous experience and the wide array of differences in physical appearance and behavior between breeds and individuals may compound the problem and increase the uncertainty and anxiety. Some extremely bold or assertive dogs will fight rather than back down when challenged. Assertive dogs may be overassertive and/or overprotective if the owners do not have good verbal and physical control. If the dog pulls the owners along during walks, it will take the lead in reacting to stimuli that it meets along the way, rather than looking to the owner for direction and reassurance. Other dogs may be in a state of conflict, in that they are friendly or socially attracted to the other dog, but uncertain or fearful of the possible outcome. These situations of conflict or uncertainty (competing emotions) can result in aggression (see Canine Communication – Interpreting Dog Language).
This form of aggression is primarily exhibited when unfamiliar dogs are on the resident dog’s property, or what the aggressor considers his territory. Some dogs get highly aroused at the sight of other dogs on their territory and may jump fences, or go through windows or doors to get to the intruder (see Aggression – Territorial).

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