Dog aggression has been recognized as a major public health issue since the 1950s. Of the more-than 4.7 million dog bite injuries per year in the U.S., 800,000 are serious enough to require medical attention.
Young children are particularly affected by incidents of dog aggression: 60% of serious injuries -- such as disabling facial lacerations -- and 85% of fatalities take place among children under 12.
Dog aggression doesn't just result in emotional and physical human suffering. Many states hold dog owners legally and financially liable for their pet's actions. Further, biting and other aggressive behavior can lead to euthanasia.
Fortunately, most cases of dog aggression don't result in serious injury. Many aggressive behaviors can be mitigated by a combination of training and cultural practices. In order to reduce aggressive behavior, it's important to understand its causes.
All animals, including humans, use aggression -- in one form or another -- to protect their territory, their offspring and themselves, as well as to regulate the social order. Aggressive behaviors encompass a variety of actions that often follow a progressive sequence. First, the dog may freeze into a rigid stance and issue a deep, warning bark. This may be followed by lunging and mouthing without tooth pressure. The dog may then progress to growling, snarling and snapping, followed by repeated bites that puncture the skin.
Aggression has many causes, but most behavior fits into five categories:
If a dog feels threatened or uneasy, it may react aggressively. Several human actions illicit aggressive fear responses in dogs, including making prolonged eye contact, picking dogs up, bending over them or taking an object away.
Territorial aggression often takes place when a human or another pet enters a space that the dog regards as its own; dogs protect their territory by barking at or attacking intruders. Possessive aggression happens when a human or other pet approaches something or someone the dog values, such as food, another family member or a toy.
When a dog cannot access the true object of its aggression, it may focus the behavior on a person within reach. This is known as redirected aggression. Finally, dominance aggression -- while rare -- may be related to your dog's desire to exert leadership.