Are Jack Russells Aggressive?

By John Martin - February 15, 2024

Jack Russell being aggressive

If you are thinking about buying or adopting a Jack Russell dog, you might be wondering if they are an aggressive dog breed. It is a totally valid question, but the answer is not that simple.

Dog breeds do have certain predispositions, but their nature depends more on their training and how they are treated on a daily basis. Regardless, understanding aggression in Jack Russells will help you prevent and control this behavior.

Jack Russells and Aggressiveness

Jack Russells are infamous for being an aggressive dog breed. However, what most people fail to mention is that the reason behind their aggressiveness is usually the pet owner’s improper behavior or lack of socialization.

It is very common for dogs to growl at other dogs or smaller animals, but if you find your dog growling at familiar humans or you, it is a major red flag.

If you set healthy boundaries with your Jack Russell and establish ground rules, there’s no reason your dog can’t be a loving part of the family.

You need to understand all the causes behind their aggression first to prevent this behavior or to rectify this behavior if your Jack Russell is showing signs of aggressiveness.

Causes of Aggression in Jack Russells

Jack Russells have a reputation for being aggressive, but this is not really an expected behavior from them.

There can be various reasons like stress, anxiety or past trauma behind a Jack Russell dog behaving aggressively, but it is not a characteristic of the breed.

When dogs develop an aggressive nature, it does not go away on its own. The problem can become worse over time and is dangerous for you and the people around you.

Jack Russells can develop aggressiveness towards other dogs, dogs of the same sex or even towards people. It is more often than not a reflection on the owner and their ability to take care of a pet rather than a reflection on the breed.

Before you try to put an end to your dog’s aggression, it is important to understand the reason behind it. Following are the common reasons behind aggression in Jack Russells:


Fear is the biggest reason behind aggressiveness in dogs. If your dog is in an unfamiliar position and feels threatened by it, he may growl or display aggressive behavior.

Especially if he has had any past traumatic incidents and sees/hears any common elements, he will feel unsafe and retaliate with aggressiveness in a bid to protect himself.

Jack Russells are quite intuitive with their owners. If you are feeling anxious or nervous, your dog might pick up on it and start mirroring your behavior.

Your dog might also have a phobia of certain sights or noises or separation anxiety, making them display fear-based aggression in specific situations.


Possessive behavior is very common with improperly trained dogs. If Jack Russells are not trained properly, they can get possessive about their food, snapping at anyone who comes near it or about their family members, posing a danger to your friends and neighbors.

The dog learns this behavior as it grows up. There are always warning signs and when the owner doesn’t do anything to help the dog learn healthy behavior, it becomes much harder to deal with once they grow up.

Jack Russells often develop jealousy when you get a new dog or pet. They feel like they need to compete with the new member for love and attention.

In this case, your dog’s behavior can be managed with targeted training and lots of love.

Excess Energy

Jack Russells were bred as hunting dogs and thus have a lot of energy. If they are not engaged in different activities on a daily basis, they start doing other activities to spend this unused energy.

Barking, growling and aggressiveness is also a possible use of all their energy. You need to ensure that your dog gets regular exercise, otherwise, he might turn destructive.

Pack Mentality

Jack Russells have a tendency to try to act as the leader of the pack. They have a very strong pack mentality and if the owner and family members do not assume leadership roles, the dog will start to think of himself as the leader of the family.

Your dog realizes his place in the family through your behavior towards him. He needs to have a clear idea of his place in the hierarchy of the family.

Here are a few actions that can confuse your Jack Russell about his place in the family:

  • Spending too much time in contact with his bed or resting place.
  • Repeatedly picking up your dog and keeping him at the same level as everyone.
  • Lying down with the dog and playing with him aggressively or for too long.

How to Curb Your Jack Russell’s Aggressiveness

If you want to curb your Jack Russell’s aggressiveness, you need to identify the reason behind it first. Doing so can make your solution a lot more effective.

One thing you need to remember is that your dog does not know what he is doing. Avoid getting angry or frustrated with him, it will only make the problem worse.

You need a lot of patience for behavior correction with dogs. Slowly rectifying behavior through motivation and encouragement takes time and effort, so be prepared to go the extra mile.

Identifying the Problem

Identifying the problem is the first step in rectifying it. You need to observe your dog’s behavior and reactions to determine what causes them to act aggressively.

It could even be something you are doing, in which case you will need to correct your behavior. Here are a few common instances when dogs react aggressively:

  • If you are going overboard with your leadership role and trying to exert dominance over your dog by forcing him to do different things, it can make him aggressive. For example, if your dog was previously allowed on the furniture and you try to force him to get off the couch out of the blue, he may respond by growling or turning aggressive. Changing behaviors and learning to obey commands takes a lot of time. If you spring unnecessary commands on your dog, he could react aggressively as he isn’t used to this new dynamic.
  • Illness or injury can also make dogs aggressive. If your dog is experiencing pain and isn’t able to convey it effectively, he can turn aggressive due to anxiety. If your dog has pain in a certain body part and you try to do an exercise or activity with him, he might act aggressively towards you when he feels pain.
  • Jack Russells are hunting dogs and thus have a very strong protective instinct. If they see certain sights or sounds as threatening, they will turn aggressive in a bid to protect you from danger.
  • If your dog sees something he’s afraid of or sees something that hurt him in the past, it can make him act aggressively.
  • Jack Russells are often reported to act aggressively towards new puppies or other animals in the house. They feel anxious about their place in the house with the arrival of a new pet and act out due to jealousy and fear.
  • Your behavior makes a huge difference in your dog’s behavior. If you cannot convey your love and affection for your dog in a healthy way, it can make them act aggressively. Your Jack Russell might growl, bark or jump at you.

Ways to Reduce Aggression

Here are a few tips to manage your Jack Russell’s aggressive behavior:

Motivate with Food

Food is a great motivator for dogs. Your dog will learn to obey any command if you reward him with food.

Feeding your dog by hand is a great way to reduce his possessiveness around food and to make him less aggressive towards you.

You can also use food or treats to train him. Ask him to sit or do a few basic treats before you give him food so that he understands that he needs to work for food.

Discourage Jumping

Jack Russells are a small-sized breed and are unlikely to do much damage by jumping on people, but you should still put an end to this behavior.

It is not a good way to maintain the hierarchy of the house if you let your dog jump on you. Visitors to your house might also not appreciate it if your dog jumps on them whenever they walk in the house.

If you let your dog work out his excitement through games or other activities, he is less likely to jump on people. Go for long walks, teach him basic commands and play different games to divert his energy elsewhere.

Teach Non-Aggressive Behavior

Dogs that did not get enough socialization when they were puppies show aggressiveness in their adult life. Adopted or rescue dogs are often aggressive due to this reason.

Don’t worry, this does not mean that it can’t be fixed. First of all, you need to create a positive atmosphere for the dog and slowly help him understand that there is no need for his aggressiveness.

Gradually, you can positively reinforce healthy behavior to make him understand what is expected of him. It will take some time, but you can successfully teach non-aggressive behavior through positive reinforcement.

Put an End to Biting in the Early Stages

Teething puppies like to playfully bite their owners during playtime. It might not hurt then, but they will register biting as acceptable behavior, which can be dangerous.

If your puppy bites you, close his mouth or put a toy in his mouth. It will convey to him that biting people is not okay, but he can bite his toys.

Keep Him Busy

Jack Russells are very hyper and can turn pretty destructive if you don’t give them enough outlets for their energy.

If it feels like your dog is not getting enough activity, go on more walks with him. You can also extend the duration of your walks to give him a challenge every now and then.

Jack Russells usually love the water and like going swimming. If you know how to swim and have access to a pool, this is another activity you can do with your dog.

Consult a Trainer

Lastly, you can consult a professional dog trainer to put an end to your dog’s controlling behavior. Dog trainers have the solutions to many different problems and have experience dealing with aggression issues.

If you have tried all the above methods and haven’t been able to control your dog, it is definitely time to consult a dog trainer.

Final Thoughts

Aggression in dogs is a very tough issue to tackle and endangers everyone who comes in contact with the dog.

Certain dog breeds like pit bulls and Jack Russells get a bad rap for being aggressive, but aggression has very little to do with the breed and more to do with the owner’s behavior and the dog’s environment.

Observe your dog to understand why he is acting aggressively. Once you get to the root of the problem, there are several ways to put an end to his aggression.