This is such an important question because it’s important for owners to understand how a Chihuahua really sees things. The truth is that there is a fine line here. You’ll see a lot of sources talk about how this tiny dog has no idea of his small stature (a big dog in a little body), but this is not entirely accurate.
Dogs are aware of their relative size and while they may not be cognitive of this to the degree that a human can be, they are quite cognizant that other dogs are larger, that people reaching down to pat them are larger, etc. So, this does play into things a bit.
This said, the extent to which a Chihuahua fears his world is almost always directly related to 3 things:
- His past experiences
- The level of desensitization that he has had
- The level of socialization that he has had
Let’s see how these 3 things work together to either increase or decrease a Chihuahua’s fear:
The more that a dog experiences events and situations and has interactions, as long as those instances are not perceived as negative experiences, the less that he is going to be afraid of them. Each time that something occurs or he meets another dog, etc. if the outcome is either neutral or favorable, a bit of the fear associated with it will be chipped away.
Then a dog is very gradually exposed to a trigger that scares him this is referred to as desensitization and when a dog interacts with something (other animals, people) this is referred to as socialization.
Some of this happens naturally; each day brings about new opportunities to become accustomed to things. So, a puppy will be more fearful than an adult and a dog that lived a shelter life or was neglected will be much more afraid than a dog that lived in a calm, happy yet eventual household.
Most Common Fears - While a puppy or dog can be afraid of just about anything, most typically this breed will be scared of cars, people outside of the household and of other dogs. Being wary of other dogs is not necessarily a bad thing; it is valid in some cases.
While it is nice for a dog to be able to play with others, unless you fully know and trust a larger dog, we recommend that a Chihuahua only play with dogs of a similar size. Far too many Chihuahuas have been attacked by larger dogs at dog parks that did not have separate areas based on size.