A dog that runs back and forth barking and snarling at another dog from behind a fence might need training on how to eliminate his dog fence fighting aggression. Fenced in animals do not get the luxury of meeting in the usual way. Because of this, there is a tension that cannot be alleviated.
If a dog is left by himself all day, then sometimes he will try to make his own entertainment. One way he might go about this is by fence fighting. The dogs involved may not even really want to injure each other, but just are frustrated that they are separated. They have just found an activity to occupy their time. If you have an inside dog, and the aggression only begins when he is outside, then it may be caused by the outdoor dog.
Fence fighting can be an annoyance for the neighbors as well. Neighbors do not like to hear the dogs barking and squawking either. If they get too annoyed, then you may have bigger problems than just the dog aggression. The police may become involved which can result in animals being put down. If children live in the surrounding areas, you can multiply your problems.
Dogs are territorial; therefore they have a natural instinct to claim territory and objects. Violence between animals is usually the result of an infringement on that territory. This can especially be evident if the dog is an inside dog and doesnt get the opportunity to socialize with other animals or people. If the dog was taken from his litter while too young, or if he was not introduced to other canines and puppies during his developmental months, then the result can be disastrous. Fence fighting aggression, like many other dog behavior issues, is usually a result of some void in the dogs previous training or rearing. However, there are many training courses and professional assistance available online and in your area.
There are three ways you can attempt to rectify your dogs fence fighting issues. One would be the direct method. Ask the owner if a meeting would be possible between the dogs in question. This will give the dogs the chance to meet one another and to establish the terms on which they will continue. The next option would be the indirect method. Outdoor scheduling might be an option, so that the two are never out at the same time. A wall to separate the dogs may be another approach. If they cant tell that the other dog is around, then the problem might solve itself. These methods might work, but your best bet is to look into training methods and solutions for long term progress. Certain gadgets, such as electrical fence barriers and specialty collars will help rectify your dogs fence fighting aggression.