The Dunbar Bite Scale :The 6 Levels of Dog Bites
Dr. Ian Dunbar’s Bite Scale allows us to get an objective assessment of how dangerous a dog actually is. It allows us to determine the severity of a dog’s bite based on an impartial evaluation of the amount of injury caused. The biting incident is then assigned to one of 6 levels. This allows us to put the situation into context and develop a reasonable prognosis about how much time, skill and risk could be expected in the rehabilitation of this dog.
Just as Stanley Coren has devised a ranking for dog intelligence, the veterinarian, canine behaviorist and trainer Dr. Ian Dunbar has a system to classify dog bites. Although the system is not infallible and there are variations, it is a good way to check the severity of the the injury.
If you have been bitten by a dog, you should know the 6 levels of dog bites according to the Dunbar scale. AnimalWised explains these 6 levels and what sort of action is required to prevent serious injury.
The Dunbar bite scale
A happy and healthy dog with no reason to feel threatened or insecure has no reason to bite. While the many factors which lead to a dog biting someone may be complicated, there is usually a reason behind the behavior. These are multi-faceted, but their training, socialization and education are usually the most important.
Dr. Ian Dunbar’s bite scale takes into consideration both the reasons why a dog may bite a human and what can be done about it. The bite scale levels are:
- Level 1: aggressive but no skin contact.
- Level 2: teeth make contact, but do not break the skin.
- Level 3: a single bite with shallow wounds.
- Level 4: a single bite with deep wounds.
- Level 5: multiple bites with deep wounds.
- Level 6: death of the victim and/or flesh consumed.
The Dunbar Bite Scale
Dr. Ian Dunbar’s Dog Bite Scale
Dogs should learn bite inhibition. This is when they grasp someone or something with their mouth, but know not to bite hard. The following levels range from dogs with bite inhibition to those with none. Keep reading to find out more.
Level 1: aggressive but no skin contact
While we are discussing the different levels of dog biting, the first does not actually involve biting the skin of the person. It is generally an aggressive display which includes biting at the air and grunting, but not any physical damage. Frequently, they involve aggressive signals such as showing their teeth and growling, although they may not even approach the person. However, if the dog snaps and bites the person’s clothing without harming their body, this would fall into the level 1 category.
Signs of aggression may seem troublesome, but if a dog uses level 1 biting, it may be simply using its canine instincts to signal fear. Over 99% of altercations which a dog do not go past level 1[1]. The dog may be scared for valid reasons if someone is trying to attack them. However, the majority of cases are to do with insecurity in the dog. Addressing the cause of the insecurity and implementing training is usually enough to prevent this kind of behavior.
Level 2: teeth make contact, but do not break the skin
With this type of biting the victim may have teeth marks, but they will not have any perforation in their skin. Virtually all people who work extensively with dogs have incurred this type of bite. These include trainers, vets, groomers and even many dog guardians. Although the dog may have bite inhibition, the person may receive bite marks or scratches. Superficial marks may appear on the skin, but the skin should not be perforated.
In these cases, the dog is sending a very serious signal that it is being subjected to some type of stress. Furthermore, it is unable to channel this stress into a healthy outlet. The dog is not intending to cause any harm and it is not a dangerous dog. On the contrary, biting without breaking the skin shows the dog has learned how to inhibit their bit properly. It should not even require first aid.
Regardless, the dog is being aggressive and we need to address this problem. We can do this by determining the cause of their stress and eliminating it from their environment. However, if the problem is not solved, aggressiveness can increase and result in a higher numbered bite on the Dunbar scale.
Level 3: a single bite with shallow wounds
The third level of the Dunbar bite scale results in a bite which causes between one and 4 superficial perforations of the skin. The wounds do not exceed deeper and half the length of the canine teeth. There may be lacerations in one direction as the victim or the dog tries to back away from the altercation.
This type of bite is variable and can have many causes. Dogs may bite because:
- They are afraid
- Rough play escalates into aggression
- The dog’s predatory instinct is triggered
- They received trauma
- Poor socialization
- Other causes
Beyond the causes and context of the situation, any dog which causes a level 3 bite should be taken to a veterinarian or canine educator. The treatment received will depend on the reasons for the incident. If the cause is clinical, they will be required to see a veterinarian specialized in canine behavior. If the cause is a behavioral problem, a canine educator or ethologist will be required.
Dogs whose bites fall into this category usually have poor bite inhibition, poor dog socialization or some other serious problem. The problem can often be solved, but it must be dealt with by people experienced in canine aggression.
As a note, the type of training is important. Some trainers are proponents of dominance theory. Although effective in the short-term, dominance training often has negative consequences in the long-term.
Level 4: a single bite with deep wounds
When the dog bites only once, but the wounds are deep, it will be considered a level 4 bite. The bite may cause one to four perforations which are deeper than half the length of the canine tooth. Injuries may go in both directions, caused by the victim removing their hand while being bitten or the dog shaking their head when biting. In some cases, these bites may be caused by predatory instincts. Dogs shake their heads when biting to cause maximum damage to their prey, so these are serious bites.
The cause is also often fear. It usually occurs in dogs which try to defend themselves against what they perceive as a serious threat, although they evade the situation after the first attack. Any dog which has given a perosn a fourth level bite needs to be seen by a professional trainer. As with dogs which have perpetrated third level bites, they will need either clinical or behavioral treatment methods, whichever is most appropriate.
In some canine sports such as schutzhund or mondioring, bites similar to the fourth level are actively sought after as a function of the game. However, they are directed toward people wearing a protective sleeve or suit. Dogs which are properly trained to play these sports are not dangerous and have bite inhibition. These dogs know they are only authorized to bite the protective suits and do not attack unprotected regions of the body.
However, there are too many dogs which are improperly trained for attack. They do not release their bite on command and ma not have control over their predatory instincts. These dogs are dangerous and should not be involved in this kind of training or gameplay.
Level 5: multiple bites with deep wounds
Fifth*level bites cause deep wounds, similar to the previous stage. However, they occur multiple times and can happen in multiple regions. This could be due to the dog making multiple bites in a single attack or due to being attacked several times over a prolonged incident
Dogs which perform fifth-level bites on the scale are considered dangerous dogs. Their rehabilitation is possible, but always under constant supervision by an ethologist, veterinary specialist or dog trainer.
Of course, there are mitigating circumstances for bites of this type. A dog that is mistreated and bites to defend itself should not be considered dangerous. This may also be applicable to situations in which the dog bites to defend their owner from an attack.
Level 6: death of the victim and/or flesh consumed
The sixth and final level of bite is the most severe. It is also important to note this level is very rare. A dog reaches the sixth level when they have resulted in the death of the victim or if they have consumed flesh which they have removed from the victim. The consumption of human meat from a pre-deceased corpse does not fall into this category.
A dog or group of dogs which is involved in the death of a person must be evaluated. However, for both levels 5 and 6, Dr. Dunbar himself claims the dogs are ‘simply not safe around people’ and even goes as far to recommend euthanasia for the dog[2]. In these cases, the authorities will likely get involved to determine responsibility for the death.
Usefulness of bite classification
This classification, as with all those which have to do with animal behavior, is a general guide. It must be considered in the specific context of a given situation where a dog bites a person. We also need to rely on experts and their assessment of a given situations which involves canine aggression. It is not a blanket approach which is applicable to every case of a dog bite.
The dogs which have bitten at the first two levels should be relatively easy to solve, especially by competent professionals. The result may need to be temporary or permanent changes to their environment. Level 3 and 4 bites require greater precautions and above this are serious incidents which often lead to criminal prosecution.
Once you understand dog bite types and learn how medical professionals assess bite severity, you can ensure effective dog bite treatment. The most widely accredited method for understanding dog behavior and analyzing dog bites is the Dunbar Dog Bite Scale, created by Animal Behaviorist and Veterinarian Dr. Ian Dunbar. The Dunbar Dog Bite Scale is an evaluation tool used in scientific analysis and clinical review for dog bite cases. The Dunbar Dog Bite Scale spans six levels, with each level corresponding with a higher degree of bite severity than the previous one.
What Is a Level 1 Dog Bite?
A Level 1 Bite involves aggressive behavior but no skin contact. Under the Dunbar Scale, a Level 1 Bite is considered a dog trying to scare the victim so that person will leave the immediate area.
What is a Level 2 Dog Bite?
A Level 2 Dog Bite is when a dog bites the skin but does not puncture the outer layer. This is considered aggressive dog behavior. The dog is likely agitated.
What is a Level 3 Dog Bite?
Level 3 Dog Bites are the initial level for wound treatment. A Level 3 Dog Bite involves one to four tooth punctures in the skin from a single bite with punctures less than half the length of the dog’s canine teeth. Most dog bite cases meet this level. At Level 3, a dog presents a significant potential danger to people.
What is a Level 4 Dog Bite?
A Level 4 Dog Bite under the Dunbar Dog Bite Scale is one to four skin punctures from a single bite, with at least one puncture deeper than half the length of a dog’s canine teeth. If you suffer a Level 4 Dog Bite, you’ll likely experience deep bruising around the wound. Dogs that inflict this level of bite should be separated from people and other animals until their behavior and the bite case are analyzed.
What is a Level 5 Dog Bite?
A Level 5 Dog Bite involves multiple Level 4 bites over several attacks. If a dog has inflicted multiple Level 4 Dog Bites with multiple bites that have a puncture wound deeper than half of the dog’s canine teeth, dog behavioral experts recommend the dog be euthanized due to its potential danger.
What is a Level 6 Dog Bite?
A Level 6 on the Dunbar Bite Scale is when a dog kills a victim in an attack. Although this level of dog bite and attack is rare, there were 62 deaths in 2022 due to dog attacks in the United States. The 62 deaths represent a new record for documented fatal attacks throughout the country.
When Should I See a Doctor After a Dog Bite?
If you’re the victim of a recent dog bite, the severity of the attack and the type of bite you suffered is only one element to consider when evaluating whether you need to see a doctor. Visit your local emergency room or urgent care center if:
- Your dog bite pain is getting worse with time
- You’re having trouble moving the impacted area of your body
- You have swelling around the dog bite
- There are red streaks on the skin coming away from your dog bite wound
- The skin around the bite changes color
- If you’re unable to obtain the dog’s rabies immunization records
Pay close attention to how you’re feeling in the days after you are attacked. If you have questions about the bite wound, visit your local doctor, emergency room, or urgent care clinic. Our recent post regarding dog bite injury care explains more about the progression of dog bite injuries and why you should book an assessment at the early stages.
Compiled & Shared by- Team, LITD (Livestock Institute of Training & Development)
Image-Courtesy-Google
Reference-On Request.
