What is human-directed aggression? By Will Bangura, M.S., CBCC-KA, CPDT-KA, (Dog Behaviorist) Certified Behavior Consultant. Human-directed aggression (HDA) in dogs refers to aggressive behaviors exhibited by dogs towards humans, which can range from growling and barking to biting. HDA is a serious issue that can have severe consequences for the dog and the humans involved. The prevalence of HDA in dogs varies depending on the study and population sampled, with studies finding that a significant proportion of HDA is directed toward immediate family members, including children. The causes of HDA in dogs are numerous. They can include medical conditions such as thyroid disorders, Cushing’s disease, neurochemical imbalances, lack of socialization, past trauma, sensory deficits, and canine cognitive dysfunction. Understanding the causes and risk factors associated with HDA is crucial to prevent and addressing these behaviors, as dog bites can result in serious injuries, infection, and even death.
Types of Human-Directed Aggression in Dogs.
Dog Aggression towards humans or Human-directed aggression in dogs can manifest in different ways, each with its unique triggers and behaviors. The different types of aggression include fear aggression, territorial aggression, possessive aggression, and predatory aggression. Sometimes there is dog aggression towards owners or dogs with stranger aggression.
- Fear aggression in dogs towards strangers. Fear aggression is a common form of aggression that arises from a dog’s fear or anxiety toward people. This can occur due to a lack of socialization, negative experiences, or genetic predisposition. Symptoms of fear aggression may include growling, barking, snarling, and biting. (American Veterinary Society of Animal Behavior, 2008), (Horwitz, 2018).
- Territorial aggression occurs when a dog perceives an individual or group as threatening its territory or property. This type of aggression may be triggered by visitors to the home, mail carriers, or strangers in the neighborhood. Symptoms of territorial aggression may include lunging, barking, and biting. (Horwitz, 2018)
- Possessive aggression is a type of aggression where a dog displays aggressive behavior when it perceives a threat to its resources, such as food, toys, or a preferred resting spot. Symptoms of possessive aggression may include growling, snarling, and biting. (American Veterinary Society of Animal Behavior, 2008), (Horwitz, 2018)
- Predatory aggression is a type of aggression that occurs when a dog sees a human as prey. This type of aggression is more common in dogs with a strong prey drive, such as hounds or terriers. Symptoms of predatory aggression may include stalking, chasing, and biting. (Horwitz, 2018)
How Prevalent is Human-Directed Aggression?
The prevalence of HDA in dogs varies depending on the study and population sampled. One study found that 5.1% of dogs in a general population showed some form of aggression toward humans (Fatjó et al., 2007). Another study found that 12% of dogs seen at veterinary behavior clinics showed aggression toward humans (Landsberg et al., 2003). Overall, the prevalence of HDA appears to be relatively low but still a significant concern.
What percentage of Human Directed Aggression is Directed at Immediate Family Members?
Studies have found that a significant proportion of HDA is directed toward immediate family members, such as owners or household members. One study found that 30% of dogs with a history of aggression toward humans showed aggression toward their owners (Fatjó et al., 2007). Another study found that 53% of dog bites occurred within the family unit (Reisner et al., 2011). These findings highlight the importance of understanding and addressing HDA toward family members.
What percentage of Human Directed Aggression is directed toward children?
Children are at a higher risk for dog bites and HDA than adults. One study found that 68% of dog bites in children were to the head and neck (Oehler et al., 2009). Another study found that children under five were the most common age group to be bitten by a dog (Gilchrist et al., 2008). The percentage of HDA specifically directed toward children is not well established, but it is clear that children are vulnerable.
What percentage of human-directed aggression is directed at strangers versus people the dog knows?
The proportion of HDA directed towards strangers versus people the dog knows varies depending on the study. One study found that 26% of dog bites occurred to strangers (Gilchrist et al., 2008). Another study found that 68% of dog bites occurred at the dog’s home or in a familiar place (Reisner et al., 2011). These findings suggest that dogs may be more likely to show HDA towards people they know but that stranger-directed aggression is still a concern.
How many people get bit on average each year by a dog?
Estimates of the number of people bitten by dogs each year vary depending on the source. The Centers for Disease Control and Prevention (CDC) estimates that 4.5 million dog bites occur yearly in the United States (CDC, 2021). However, this number is likely underestimated, as many dog bites go unreported.
How often does someone get bit by a dog?
The frequency of dog bites also varies depending on the population and location. One study found that the annual incidence of dog bites requiring medical attention was 12.9 per 10,000 people in a large urban area (Weiss et al., 2018). Another study found that the incidence of dog bites resulting in hospitalization was 0.4 per 10,000 people in a rural area (Loder et al., 2015). These numbers highlight the need for increased awareness and prevention of dog bites.
What percentage of dog bites require medical attention?
The percentage of dog bites that require medical attention varies depending on the severity of the bite. One study found that 12.4% of dog bites required medical attention, including sutures or antibiotics (Weiss et al., 2018). Another study found that 34% of dog bites resulted in medical treatment, such as wound care or antibiotics (Gilchrist et al., 2008). It is important to note that even minor bites can lead to infection and should be properly cleaned and treated.
How often is a child admitted to the emergency room for a dog bite?
Children are more likely than adults to require medical treatment for dog bites. One study found that children under five were more likely to require emergency room treatment for dog bites than any other age group (Gilchrist et al., 2008). Another study found that children were more likely to be hospitalized for dog bites than adults (Kann et al., 2001). These findings highlight the need for increased awareness and prevention of dog bites, particularly among children.
What Causes Human Directed Aggression?
There are numerous causes of human-directed aggression in dogs. This article will discuss the different medical conditions, neurochemical imbalances, lack of socialization, past trauma, sensory deficits, and canine cognitive dysfunction that can lead to human-directed aggression in dogs.
Thyroid disorders can cause behavioral changes in dogs, including aggression. Hypothyroidism, the most common thyroid disorder in dogs, can lead to lethargy, weight gain, and behavioral changes such as aggression towards people and other dogs. Conversely, hyperthyroidism can lead to restlessness, anxiety, and irritability, manifesting as aggression towards humans and other animals. (Keeble & Debenham, 2018)
Cushing’s disease is a hormonal disorder that can cause increased cortisol levels in dogs. The excess cortisol can cause behavioral changes, including aggression towards humans and other dogs. (Dodman & Shuster, 2019)
Addison’s disease is a hormonal disorder that can cause a dog’s cortisol deficiency. This can result in lethargy, weakness, and in some cases, aggression toward humans and other animals. (Keeble & Debenham, 2018)
Dogs in pain can become aggressive toward people who attempt to handle or touch them. Painful conditions such as hip dysplasia, arthritis, dental issues, or infections can cause dogs to become aggressive. (Overall, 2013)
Pregnancy and maternal aggression.
Female pregnant or nursing dogs can become aggressive towards humans or other animals if they feel their offspring are threatened. Maternal aggression is a natural behavior in dogs and can be triggered by various stimuli, including unfamiliar people or animals, loud noises, or sudden movements. (Keeble & Debenham, 2018)
Neurotransmitters are chemical messengers that transmit signals within the nervous system. An imbalance in these neurotransmitters can cause behavioral changes, including aggression (Overall, 2013; Dodman & Shuster, 2019.) The following neurotransmitters can be involved in human-directed aggression:
Serotonin is a neurotransmitter responsible for regulating mood and behavior in dogs. A lack of serotonin has been linked to aggressive behavior in dogs.
Dopamine is a neurotransmitter that is responsible for regulating reward-motivated behavior in dogs. Imbalances in dopamine can lead to impulsive or aggressive behavior.
Norepinephrine is a neurotransmitter responsible for regulating arousal and attention in dogs. An excess of norepinephrine can lead to hyperactivity, anxiety, and aggression.
Gamma-aminobutyric acid (GABA) is a neurotransmitter inhibiting neuronal activity in dogs. A lack of GABA has been linked to anxiety and aggression.
Acetylcholine is a neurotransmitter responsible for regulating dogs’ memory and attention. Imbalances in acetylcholine can lead to memory impairment and aggressive behavior.
Other Stress Hormones.
Stress hormones such as cortisol can also play a role in human-directed aggression in dogs. Elevated levels of cortisol have been linked to aggression in dogs.
Lack of Early Socialization and Exposure.
A lack of early socialization and exposure can make dogs fearful of people or unfamiliar situations. Fear can manifest as aggression, and dogs fearful of humans can become aggressive toward them. (Mills & Beral, 2017)
Past trauma is another factor that can contribute to human-directed aggression in dogs. Dogs subjected to abuse, neglect, or traumatic experiences in the past may be more prone to aggressive behavior toward humans. This can be due to a heightened sense of fear or anxiety and a lack of trust in people (Overall, 2013).
Sensory Deficits in Hearing or Vision.
Dogs with hearing or vision deficits may become startled or defensive when they are approached or touched by people they cannot see or hear. This can cause them to become aggressive toward people. (Mills & Beral, 2017)
Canine Cognitive Dysfunction.
Canine Cognitive Dysfunction (CCD) is a condition that affects older dogs, and it is similar to Alzheimer’s disease in humans. Dogs with CCD may become disoriented, anxious, and confused, showing signs of aggression toward people. (Campbell, 2018)
Treating Human Directed Aggression.
Prevention is key when it comes to human-directed aggression in dogs. Early socialization and training can help prevent fear and aggression toward humans. Puppies should be exposed to various people, animals, and environments positively and controlled. This can help them develop confidence and learn appropriate behavior around people. It is important to teach puppies to greet people calmly and politely and discourage aggressive behavior toward them. (Klinghammer, 2014; Landsberg et al., 2013)
Treat any underlying medical conditions.
Medical conditions like pain, thyroid disorders, and neurological issues can contribute to dog aggression. It is important to rule out any medical conditions that may be causing or contributing to the aggression and treat them accordingly. In some cases, treating the medical condition can resolve the aggression. (Overall, 2013; Horwitz & Mills, 2009)
Management and Safety.
Dogs exhibiting human-directed aggression should be managed and kept safe at all times. This may involve using a muzzle, keeping the dog on a leash or in a secure area, and avoiding situations that may trigger aggression. The goal is to prevent the dog from causing harm to people or other animals while the underlying issues are being addressed. (Overall, 2013; Horwitz & Mills, 2009)
Positive reinforcement training.
Positive reinforcement training is a non-punitive and effective method for modifying a dog’s behavior. This involves rewarding the dog for desirable behavior and ignoring or redirecting undesirable behavior. Using high-value treats and rewards to reinforce the desired behavior is important. Positive reinforcement training can help build the dog’s confidence, reduce fear and anxiety, and improve their behavior toward humans. (Pryor, 1999; Yin, 2009)
Differential reinforcement training.
Differential reinforcement training involves reinforcing an incompatible behavior while ignoring the aggressive behavior. For example, a dog may be trained to sit or lay down when a person approaches, which makes it difficult for the dog to show aggression toward them. This method can help the dog learn alternative behaviors that are more desirable than aggressive behavior. (Overall, 2013; Horwitz & Mills, 2009)
Counterconditioning and desensitization.
Counterconditioning and desensitization involve gradually exposing the dog to the trigger (in this case, humans) in a controlled and positive manner. This can help the dog form a positive association with humans and reduce their fear or aggression towards them. For example, the dog may be exposed to people from a distance at first and then gradually brought closer over time as the dog becomes more comfortable. (Overall, 2013; Yin, 2009)
Look at that dog training.
Look at that dog training involves teaching the dog to look at a person or object that would normally trigger their aggression and then rewarding them for looking away from the trigger. This can help the dog learn to control their impulses and reduce aggression toward humans. This method can be especially useful for dogs that are fearful or anxious around people. (Stilwell, 2009; Landsberg et al., 2013)
The engage disengage training.
The engage disengage training involves teaching the dog to engage with a person or object that would normally trigger their aggression, then disengage and move away from the trigger. This can help the dog learn to control their impulses and reduce aggression toward humans. This method can be especially useful for dogs that are overly excited or aroused around people. (Yin, 2009; Landsberg et al., 2013)
Behavior Adjustment Training (BAT).
Behavior Adjustment Training (BAT) is a technique that involves teaching the dog to make choices and control its behavior in situations that would normally trigger its aggression. This is done by gradually exposing the dog to the trigger in a controlled and positive manner while allowing the dog to choose how to react. The dog is rewarded for calm and appropriate behavior, and the trigger is removed, or the distance is increased if the dog becomes anxious or aggressive. (Grisha Stewart, 2011; Landsberg et al., 2013)
Finding a Dog Behaviorist or Dog Trainer for Dog Aggression.
If you’re dealing with a dog that is displaying problematic behavior, seeking the assistance of a professional dog behaviorist can be invaluable. However, finding the right person for the job is crucial. Here are some steps you can take to find a qualified and trustworthy dog behaviorist, as well as some red flags to look out for when choosing a trainer or behaviorist.
Do Your Research.
Start by researching local dog behaviorists online. Look for professionals with a lot of positive reviews from previous clients. You can also check with organizations such as the International Association of Animal Behavior Consultants (IAABC) or the Association of Professional Dog Trainers (APDT) to find certified trainers.
Check the credentials of potential behaviorists or trainers. Look for someone with a formal education in animal behavior or psychology. Many qualified professionals have a degree in a relevant field, such as veterinary science or animal behavior. You can also look for someone with certifications from reputable organizations, such as the Certified Applied Animal Behaviorist (CAAB) or the Certified Professional Dog Trainer (CPDT).
Ask for Referrals.
Ask friends, family, or your veterinarian if they can recommend a qualified behaviorist or trainer. Personal recommendations can be very helpful.
Interview Potential Candidates.
Once you’ve found a few potential behaviorists, schedule a phone or in-person interview. Ask about their experience, training methods, and their philosophy on dog behavior. Ensure you feel comfortable with their approach and that it aligns with your beliefs.
Observe a Training Session.
Ask to observe a training session or two before committing to working with a behaviorist. This will allow you to see their methods in action and evaluate whether they are a good fit for you and your dog.
Red Flags to Look Out For.
While many dog behaviorists and trainers are trustworthy and professional, there are some red flags to look out for.
- Avoid anyone who uses harsh or abusive training methods. These can include physical punishment or methods to scare or intimidate the dog.
- Be wary of trainers who guarantee quick results or use a one-size-fits-all approach. Each dog is unique, and the right training approach will depend on the dog’s individual needs and personality.
- Steer clear of anyone unwilling to answer your questions or explain their methods. A good behaviorist or trainer should be transparent about their approach and open to client feedback.
- Be cautious of anyone who claims to be a “miracle worker” or who makes unrealistic promises. Changing problematic behavior takes time and effort, and no overnight solutions exist.
Human-directed aggression (HDA) in dogs is a serious issue that can have severe consequences for both the dog and the humans involved. The prevalence of HDA varies depending on the study and population sampled, but it is clearly a significant concern. Studies have found that many HDA is directed toward immediate family members, including children. Children are a vulnerable population, and they are at a higher risk for dog bites and HDA than adults. The causes of HDA in dogs are numerous and can include medical conditions, neurochemical imbalances, lack of socialization, past trauma, sensory deficits, and canine cognitive dysfunction. Understanding the causes and risk factors associated with HDA is crucial to prevent and addressing these behaviors, as dog bites can result in serious injuries, infection, and even death. Increased awareness and prevention of dog bites, particularly among children, is necessary to reduce the number of injuries and fatalities caused by HDA in dogs. Owners should take responsibility for providing proper training, socialization, and medical care to their dogs to prevent HDA. It is also important to seek professional help if a dog exhibits HDA to address the issue before it escalates into a more serious problem.
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