It is a tradition as old as time; so common that it is used in all forms of media, from cartoons to movies. It is seen as something that just is. But the question for many people is why do they do that?
It is especially true of those owners who have both animals and they get along well. So it seems odd to them that when another dog chases after their cat, they don’t understand exactly why.
The cause of this is instincts. Not necessarily to chase cats in particular, but to chase anything that moves. More so if the thing that is moving is smaller than they are.
In the wild, that is how dogs would catch their food; they would chase after their prey to catch it. We see this behavior in wolves and some feral dogs today, who still hunt for their food. It is essential to their survival for wild dogs to hunt; few wild dogs are scavengers.
This instinct is called the ‘prey drive’ and is embedded in all dogs, even after ten thousand years of domestication. With some dogs, the prey drive is weak, even practically non existent, there are many other dogs where the instincts are still rich. Hunting dogs, such as hounds, retrievers, and terriers, just to name a few.
These were dogs that were bred to maintain the prey drive, and these are breeds of dogs that are usually the most likely to chase cats. Terriers, dachshunds and many hounds have been the last breed to begin to be bred away from hunting.
The very prey drive that makes dogs chase cats is triggered by movement. So it’s not that the dog see the cat as prey, it’s the movement that ignites their instincts. For similar reasons, the same dog may chase squirrels, rats, or rabbits. This instinct also causes them to chase after and ‘fetch’ sticks, or toys. They see it as prey, and they bring it back to you to share their ‘kill’.
Movement is not the only trigger for some dogs. Smell is far less common, but it is a common reason as well, more so in hunting dogs. There are other ways that the hunting instinct manifests, for example, greyhounds are trained to chase a mechanical rabbit around the track, and herding dogs chase the herd they are ‘in charge’ of.
This brings up the question, however, of why do some dogs not chase cats; as well as why do some dogs not chase the cats they live with? The answer is largely breeding and socialization.
After thousands of years of domestication, dogs have slowly been weaned off of the need to hunt for their food. While some breeds maintained that prey drive for various different tasks, such as killing rats, helping hunters, or protecting farmlands, their main objective was no longer to kill for food.
Since the Victorian Era, dog breeding has become more selective as dogs have gone from being a working animal to a companion. The demand for more passive dogs began, and some breeds were preferred with a calmer temperament.
The need for dogs with a prey drive decreased, and for many dogs, the result is a very low drive. This is a very common reason that dogs do not chase cats.
Another reason dogs do not chase cats is socialization. If the dog was raised with cats from the age of a puppy, or the owner slowly socialized the two pets, the dog sees the cat as part of the pack rather than possible prey. This is why dogs that can be seen chasing the neighbor’s cats might not even bat an eye when it’s housemate runs by.
The more familiar the dog is with cats, and the lower the natural prey drive is, the less often the dog will give chase to the cat.
Most dogs who chase cats, if they caught them, would simply corner them and then lose interest. While this is true, if the dog has a high prey drive it is always a good idea to be careful.
It gives the dogs a natural high to chase after other animals. They may revert to their natural instincts and attack, or either pet may be injured in rough play. While the prey drive that causes dogs to chase cats and other animals in instinctual, it can be trained down if it is an issue. However, this takes time, patience and determination in order to wean the dog away from the habit.