If you're wondering why dogs do the kill shake, you most likely witnessed the behavior several times in your beloved companion.
The "kill shake" is one of the last behaviors observed in a dog's predatory sequence.
It's a motor pattern that is deeply ingrained in a dog's genetic core and has survived domestication.
If you are intrigued by this behavior, read on to discover the main purpose of this move.
A Dog's Predatory Sequence
Prior to domestication, in order for a dog's ancestors to enjoy a meal, it was necessary to follow a precise sequence which is known as the "predatory sequence."
In wolves, the predatory sequence is composed of five main motor patterns (also known as predatory behaviors) which are reliably triggered by the movement of prey.
In dogs, the predatory sequence's organization has become more "relaxed" courtesy of domestication and its associated shift from the hunter to scavenger niche (Coppinger & Coppinger 2001).
The five predatory behaviors that are part of the predatory sequence include the following: orienting towards prey, eye stalk, chase, grab bite, kill bite (or head shake), dissection and consumption.
These behaviors, classified as predatory behaviors, were not learned behaviors; rather, they came naturally as they were essential for survival purposes.
It is thanks to these instincts, and later on, the process of domestication, that we get to enjoy our dogs today!
Why Do Dogs Do the "Kill Shake?"
As seen, the kill shake takes place after chasing and grabbing, and is then followed by dissection and consumption, but what's the main purpose of the "kill shake" in dogs?
If you haven't watched many wild animal documentaries, here's a brief explanation of what really happens when a predator delivers a kill shake.
A disclaimer is warranted here though: you may want to skip this part if you are squeamish!
When predators capture prey, they have a variety of strategies to make their final kill.
With large prey animals, predators will deliver their killing bite by aiming for the throat area, tearing the animal's jugular vein, or maybe one or both carotid arteries, which ultimately leads to a fairly quick death due to massive blood loss.
Smaller animals though may be killed by simply grabbing the animal by the neck area and vigorously shaking it.
The goal is to "snap" the animal's neck. This method is therefore commonly used to kill rodents and mice.
This shaking is often referred to as the "dog death shake" or "dog kill shake."
Why Do Dogs Kill Shake Their Toys?
During playtime, dogs often demonstrate the instinct of killing small prey by shaking their toys.
As mentioned, this action mimics when dogs breaks the prey's neck and spine, ending its life quickly.
This instinct can be found in all breeds of dogs and can be even seen in young puppies.
While today's domesticated dogs don't hunt prey, they will still play with toys pretending their are prey animals.
Dog toy manufacturers know this very well, which is why they craft toys that resemble furry prey animals and some may squeak too!
Is Shaking Toys in Dogs Normal?
A dog shaking their toys is perfectly normal. Shaking is a fun activity for a dog, and it stimulates his mind.
Dogs may lift their butts, lower their bodies, in what is known as the "prey bow" and they may even growl while shaking their toys.
This again is perfectly normal and is part of the game!
Are There Other Forms of Toy Shaking?
Yes, not all dogs shake toys purposely to "kill it."
I have seen my dogs shake their toys for the sole purpose of ridding them of any sand, dirt or debris which may have attached to a wet ball or some other wet toy.
They may also do a "kill shake" when they are trying to get a better grip of a ball in their mouth or when they are trying to "free" any stuck foods from inside a Kong.
As with any other dog behaviors, context and the accompanying body language is therefore always key.
When Things Go Bad
Sadly, some dogs actually bring things to a higher level, and may use their kill shake to kill small animals such as mice, voles, baby rabbits, cats and sometimes, even small dogs.
While any dog can kill small critters, certain dog breeds may be particularly predisposed to this, such as dog breeds falling into the sighthound, lurcher and terrier category.
Such dogs were selectively bred to hunt and kill animals such as rats, hares, foxes and even gazellas.
Dogs who kill animals are often referred to as "finishers," since they go through the entire predatory sequence, from start to finish, therefore ending up finishing the animal's life.
Is There Any Hope For Dog Who Kill Animals?
Witnessing a dog who kills small critters can be traumatizing for dog owners. Things may get even more grave if the killed animal happens to be a small dog.
In these cases, is there any hope for rehabilitation? Or are these dogs dangerous killers that should be muzzle for life or put down?
Every case of course would need a close evaluation. These cases therefore warrant a deep investigation so to evaluate the exact circumstances along with the dog's behavioral history.
Has the dog killed other animals before? Does the dog appear to have a very high predatory drive? Does he act in silence? Most truly predatory dogs are very silent.
Predatory drift is a phenomenon that should be considered when it comes to large dogs killing smaller dogs in play.