Why Are Chihuahuas So Aggressive?

Reviewed By Julie •  Updated: 02/01/22 •  11 min read
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Why Are Chihuahuas So Aggressive?

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Are you the lucky pet parent of a Chihuahua? Have you been around Chihuahuas very much? If so, then you know how these feisty little dogs can be! They’re adorable, small dogs that have huge personalities! However, there are anecdotal reports that these tiny dogs can be very aggressive.

What? How or why would such a small dog be aggressive? That’s what we’ll take a look at in this article. We’ve put together some facts about Chihuahuas, why they may be fierce (and if that’s true or not!), along with how you can help your Chi not be so aggressive. Let’s get started!

What is a Chihuahua?

Chihuahuas are known for being one of the smallest dogs around and for having very feisty personalities! These small dogs also act like they believe they’re big dogs. That most likely comes from their diminutive size.

These little dogs want to be near their pet parents most of the time. They could be called “Velcro dogs” for this reason. No matter where you go, your Chi will follow along. And because Chihuahuas are so small, it’s easy for pet parents to take the dogs with them shopping, out running errands, and more.

Chis are an ancient dog breed. It’s thought they date back to the Toltec civilization. Drawings from the 9th century CE by the Toltecs show dogs that strongly resemble Chihuahuas. The dogs were called Techichi, and no one is sure what their purpose was to the Toltec people.

Later, the Aztecs conquered the Toltecs and took over breeding Chis. Many of the dogs lived in temples and were used in certain rituals. The dogs were thought to have mystic, religious, and healing powers. When the Conquistadors conquered the Aztecs in the late 1500s, the small dogs were almost lost to history. However, the dog was again discovered in Mexico in the 1850s in the state of Chihuahua. From there, the dogs’ popularity grew!

Chis are fun-loving dogs and are very affectionate with their families. They’re very intelligent and learn quickly. They excel at agility and obedience competitions. However, they can be very stubborn, territorial, and overprotective. Chihuahuas will become dominant in a home unless they understand their pet parent is the alpha leader.

What’s more, these tiny dogs will stand up to larger dogs in a very aggressive manner. For this reason, Chis require plenty of positive reinforcement training and socialization starting at a young age.

So, are Chihuahuas really that aggressive?

Chihuahuas & Aggression

Chihuahuas can be very aggressive dogs. Studies have shown that these dogs outrank Pitbulls. Pitbulls usually rank lower in aggression, despite their reputations for being the most aggressive dogs. The Chihuahua actually wins this record.

Most of the Chihuahua’s aggression stems from his small size and the tendency for this dog breed to be overly protective and territorial.

Why Are Chihuahuas Aggressive?

There are many reasons for these small dogs being aggressive. Some of these reasons may be surprising. Let’s take a look at the top issues that cause Chihuahuas to be aggressive.

1. It’s in Their Genes

The first reason Chihuahuas are aggressive is because of their genes. These dogs have been popular for years due to their cuteness and small size. They’re usually easy to care for, too. Chihuahuas do well in small spaces such as apartments.

Their very popularity has led to some genetic issues growing in this dog breed. Over time, unreputable breeders didn’t take care of the dogs that were bred. They were (and are) focused on breeding as many puppies as possible. Such breeders do not use proper breeding methods and choose parents that are unsuited for breeding. The parents may have health and personality issues that are passed down to their puppies. The result is a dog breed that’s filled with genetic problems.

Chihuahuas suffer from anxiety issues, such as separation anxiety, which can lead to aggressive behavior in this and other dog breeds. The dogs will bark to gain attention if something scares them or if they feel threatened. And they will bite to protect themselves and their territory.

In addition, this dog breed suffers from certain health issues due to improper breeding methods. Some breeders try to develop the smallest dog possible without regard for the dogs’ health. Some genetic health issues cause the dogs to live with pain and feel pretty uncomfortable, if not miserable.

2. Chihuahuas are Protective & Territorial

Chihuahuas are wonderful guard dogs because they have a natural tendency to protect their space and belongings. When these small dogs meet strangers (humans or canines), they may become defensive immediately. They will attack if they feel it’s necessary.

Chis may show these signs when they’re being territorial and protective:

These are all warning signs the Chihuahua is very upset. By the time he gets to the muzzle punch, and the tail stops wagging, the Chi may be ready to pounce and bite. If you’re near a Chihuahua that starts growling, that’s the first sign you need to back off. Otherwise, you will make the dog feel scared and threatened. He will then attack and bite.

3. Chihuahuas Don’t Like Strangers

While Chis are loving with their pet parents and family, they really are not fond of strangers. New people or dogs can make the Chihuahua scared and feel as if his territory (or favorite person) is in danger. He will then defend himself, his person, and his territory.

It can take a Chihuahua a little while to warm up to a new person, dog, or other pet. However, with proper training and socialization, these dogs can learn to be friendly rather than fearful.

4. Chihuahuas Have Dominant Personalities

Chihuahuas may be small dogs, but they have very dominant personalities. If a pet parent doesn’t teach the dog who is boss, the dog will then run the household. And a Chi definitely has the will and attitude to run the entire house! They will be in charge, and you must abide by the rules. If you don’t, then you might get bit! If the Chi is the head of the pack, you must obey!

We’re not overstating the fact that these small dogs have dominant personalities. It’s true! However, if a Chi is trained and socialized from a young age, this personality tendency can be overcome. In addition, a dog that’s not in charge will be more passive rather than aggressive.

5. Chihuahuas & Anxiety

Some Chihuahuas have not been bred with proper breeding methods, leading to dogs that have health and behavioral issues. In addition, Chis are very connected to their pet parents. Both of these tendencies can lead to anxiety in Chihuahuas.

For instance, Chihuahuas that are left alone for long periods become fearful and anxious. They may also feel bored. That’s a dangerous mix that can lead to negative behaviors such as aggression, destructiveness, and more.

Chis do better in a household where they can be near their favorite person most of the time. They also need plenty of exercise and mental stimulation to get rid of pent-up energy.

What’s more, loud noises can also cause anxiety in a Chi. Sounds such as constant construction noises, fireworks, thunder, and more can really scare these dogs.

In addition, Chihuahuas may be anxious because of past trauma they’re experienced. This can also make them more aggressive. They may have flashbacks and develop a condition similar to PTSD in humans. This can also make the dogs more aggressive.

7. Chihuahuas Don’t Like New Places

Another issue that may bring out the aggression in a Chi is that they really don’t like new places. These dogs prefer to feel secure and stable where they are now.

On the other hand, moving to a new place means new everything—from smells, pets, and people. The dog then has to get used to new favorite places and more.

8. Chihuahuas May Be Aggressive Because of Their Pet Parents

Finally, Chis can be aggressive because of their pet parents. How’s that possible? Have you ever watched videos on YouTube of aggressive Chihuahuas? If you do, you’ll quickly notice something pretty fast. The dogs’ pet parents don’t show respect for their small Chis. They think it’s cute when their small dog acts aggressively like a large dog.

If you watch some of these videos, take a good look at how the dogs react to different stimuli or situations. These poor dogs are often being aggravated and encouraged to be aggressive by their pet parents.

It may seem funny to see such a small dog become so aggressive. However, think of a larger dog acting in that way. No larger dog would be allowed to act so aggressively. And pet parents should not encourage or allow this behavior in their Chihuahuas, either.

Many Chihuahuas sadly end up in shelters across the country for these reasons. Chis and Chihuahua mixes usually outnumber all other dog breeds in shelters. The main reason is because of their aggression, and the fact pet parents were not training and socializing their dogs. That’s pretty sad.

How to Ensure Your Chihuahua Isn’t Aggressive

Is it possible to ensure your Chi isn’t aggressive or behaving badly? Yes, it is!

If you’re interested in adopting a Chihuahua puppy, then make sure to adopt from a reputable breeder. Sure, it may be cheaper to adopt from a puppy mill or a backyard breeder. However, these facilities don’t use proper breeding standards. The result is dogs that are unhealthy and have behavioral problems. So, adopt your puppy from a reputable Chihuahua breeder.

No matter where you adopt your fur baby, ensure he gets the proper training and socialization. This is imperative in all Chihuahuas. These diminutive dogs are easily frightened and anxious. Put yourself in their place! Almost everything is larger than they are! No wonder they’re fearful!

Training & Socialization are Essential

Training and socialization, especially from an early age, can help your dog to become confident and well-rounded. The goal is to have a Chi who knows you’re in control.

Socialization helps them learn how to act and behave in different environments, with new people, other dogs & pets, and more. The result is a dog that’s less fearful and is more confident. They’re also well-behaved.

When training, teach your Chi some basic commands. These include:

Provide Plenty of Exercise

These little dogs are very active and need to get outside and play! They do well walking, playing in the backyard, and more.

Chihuahuas need at least 30 minutes of walking every day. They also love to play fetch, do obedience training, and more.

Mental Stimulation

These dogs also need a lot of mental stimulation. Chihuahuas are intelligent dogs! So, be sure to offer doggie puzzles (sized for your fur baby) and more.

Provide Your Dog with Personal Space

Another thing that Chis really need is their own space. While they love to explore, they love to establish their own favorite spaces around the house.

You might consider providing your small dog with a crate or allow him to choose his own space. You can make the space more comfy with a dog bed and blankets, too.

Avoid Getting Too Many Other Pets

Chihuahuas are very demanding when it comes to attention, and they may feel ignored or left out if you have too many other pets. And they also tend to have an issue with other pets that are also dominant.

Be a Respective Pet Parent

Finally, be a respective, loving pet parent. Remember, the Chihuahua is a dog, though smaller than most dog breeds. Even so, they are still dogs and deserve respect. That doesn’t mean allowing your Chi to run the house! However, it does mean not finding his bad, aggressive behavior cute or funny.

Never laugh or encourage your dog’s aggressive behavior. This only makes him worse. Instead, be sure to use positive reinforcement training and socialization. You’ll have a better behaved, happier Chihuahua that everyone will love!

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Julie is a graduate of the University of North Carolina, Wilmington, where she studied Animal science. Though contrary to the opinion of her parents she was meant to study pharmacy, but she was in love with animals especially cats. Julie currently works in an animal research institute (NGO) in California and loves spending quality time with her little cat. She has the passion for making research about animals, how they survive, their way of life among others and publishes it. Julie is also happily married with two kids.

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