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Updated: 4 days ago

Aggressive behaviour from dogs can feel distressing and frightening. The thing to remember is that a level of aggressive behaviour is actually quite normal.

When we see dogs as perfect beings who will never growl or snap we are asking more of them than we would expect of any human.

Any dog, if put under enough pressure, could show some level of aggression. The level of tolerance varies according to the dog and the situation at the time. The level of response varies too. The following is a link to Jean Donaldson’s bite threshold model: Good dogs bite too.

Note the importance of warnings. When you punish a growl, you risk shutting down the dog’s early warning system. If you don’t then do any work on the dog’s comfort level, they will still feel uncomfortable, but you’ve told them not to tell you about it. Some dogs will cope with this. They may still feel stressed, but not bite.

Others will just bite without warning.

Warnings are useful.

They tell us we have work to do.

Once a dog bites, you may get a rude awakening, but again you have information. You know how hard they are likely to bite and whether they are likely to do damage.

Dr. Ian Dunbar established the dog bite scale of responses below. I have included excerpts from an excellent article which I found here.“The bite scale

Level 1: The dog growls, snaps or lunges at a person. The teeth never touch skin.

Level 2: While the dog’s teeth make contact with skin, there are no punctures. There may be some indents or bruising.

Level 3: There is a single bite that punctures the skin no more than half the length of the dog’s canine tooth. Typically the entry wounds are circular or teardrop shaped. If there are slashes, they only occur in one direction because the person pulled away, not because the dog shook his head. Bruising is expected.

Level 4: There is a single bite that punctures the skin more than half the length of the dog’s canine tooth. The dog bit down and held, or shook his head. Slashes occur in both directions and bruising is significant.

Level 5: Multiple bites.

Level 6: The dog consumed flesh or killed the victim.”

Ian says that the vast majority of bites happen at level 1 or 2. These dogs have excellent bite inhibition, and are not dangerous. However, these dogs do have a problem, and the problem must be solved as soon as possible to prevent someone from becoming injured.

Dogs that inflict a level 3 bite are probably dangerous, and people working with these dogs should be very careful to ensure they have the expertise needed to treat them.

Level 4 biters should be treated like a loaded gun. There need to be fail safes in place to prevent accidental exposure to people. They should not leave the house unmuzzled. They need to be locked up when people are over. Ian will not work with level 4 cases.

Although it may be possible to help these dogs, he has found that it is too difficult to get owner compliance. People simply do not do the level of management needed to keep the dogs from biting again. He recommends that level 5 and 6 dogs be instantly euthanized.

The harsh reality is that when a dog shows aggressive behaviour, they usually get what they want e.g. other dogs/ people go away. This rewards (reinforces) the behaviour, making it more likely to happen again.

To reduce aggressive behaviour first you need to avoid the situations which trigger it. At the same time you need to work on building the dog’s tolerance of whatever happened. That said, be reasonable. There are plenty of things dogs shouldn’t have to tolerate!

If a dog is anti social, try to get them out around calm dogs with strong social skills. Take the pressure for interacting off them.  Some dogs aren’t ready to meet every other dog they see and may never be. Just walking together can be an excellent start. Parallel walking is often used to help rehabilitate less socialised dogs. My own reactive dog benefited enormously from walks with a mix of people and dogs who willingly gave each other’s dogs personal space.

Just expecting dogs to ‘sort it out’ is only likely to work when you have arguments between well socialised, suitably matched playmates. If one or both dogs lack social skills or their play styles are mismatched, the result probably won’t be pretty.

Sometimes punishing aggressive behaviour in an anti-social dog will shut down the warning signals, allowing the dog to get near enough to other dogs to learn they are safe. Unfortunately, the opposite may happen. The dog may connect punishment with the presence of other dogs and the aggressive behaviour may actually get worse.

Please, please, please inform yourself about methods and risks before beginning work on your own dog’s aggressive behaviour.


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