Puppy Developmental Stages

During our classes here at CTA, we often have the opportunity to work with dogs of all ages anywhere from 8 weeks of age to adulthood. During training we observe dogs that have developed fearful behaviors or social issues that cause a great amount of frustration for handlers and on occasion can even result in dogs being washed out of trailing programs, so this year I decided to enroll in some professional dog training courses that addressed this issue more thoroughly than my own professional background and experience provided me with. I want to share a few key points from those programs, some of what I discovered about the most critical stages of puppy development and some simple things you can do to avoid creating social and environmental problems when working with new puppies and adolescent dogs that are in training for trailing work. Of course, the scope of this article does not cover all of the information I learned from two different experts on the subject, but it does explore a few important key points to help you gain a better understanding of your dog's stages of development from puppy through adolescence.


Sometimes we get in a hurry to see results for our young dogs, forgetting that they, too, have stages of development we must pay attention to and help guide them through in order to get a well rounded, reliable working dog that can calmly and fearlessly navigate its way through a very demanding urban or rural environment or handle the social pressure of a long public relations day.


According to Karen Pryor Dog Training Foundations Course (2014), Canine studies have shown that dogs go through critical periods of development when they learn certain key concepts that will affect their behavior throughout all subsequent life stages. “Many of the most critical stages of development occur in the first few months of life. Depending on the history of your dog, you may not even realize what happens in a puppy’s first few months of life”. Pryor (2014). Understanding these stages is critical for dog handlers and trainers attempting to train a puppy from the ground up. Knowing about these three puppy developmental stages can help prevent unwanted fear reactions, unacceptable social behaviors or lifelong problems down the road.


There are lots of developmental stages so for the purpose of this article we will only focus on three critical stages that can impact young dogs in training.




second fear period


By making yourself familiar with these three critical developmental periods, you can take a proactive approach to train and expose your dog to different situations that it may encounter and react to during its working life. 


“The first 12 weeks are the most important period of development in a dog's life. During that time, the canine and human socialization periods occur, as does the fear imprint period”. Pryor (2014).


What is Socialization?


From a dogs perspective, socialization is the process of learning the behavioral and social skills it needs to survive in its environment. “It is how any animal learns the key, lifesaving concept of ‘friend or foe’. Animals are more likely to respond aggressively to stimuli that fall in the ‘foe’ category, out of an instinct for self-preservation. They will tend to consider a novel stimulus dangerous if they haven’t previously learned it is safe during the appropriate life stage”. Pryor (2014).


From a handlers perspective, socialization means introducing a dog to a wide variety of situations and experiences so that it learns the things it will encounter are, for the most part, safe. It is the handler's responsibility to make sure these encounters are as fun and painless as possible for the dog during these critical stages of development.


Why socialize?


Socialization helps improve the dogs quality of life by:


solidifying your relationship with the dog.

creating a stable, confident dog.

desensitizing the dog to normal sights and sounds. Pryor (2014).


When you provide your puppy with fun, stress-free experiences in a variety of places and introduce it to different types of people and situations, you lower the chance that it will develop fearful behaviors when it encounters something new or different. by doing this, you are using a positive, proactive approach to helping your dog on its way to becoming a calm and confident working partner.


If you properly socialize your dog by slowly introducing it to sights, sounds and different people it’s likely to encounter, such as police sirens, loud vehicles, strange people, skateboarders and bicycles and wheelchairs just to name a few distractions those things will be no problem for the dog to work with later on.


Socialization period


The experiences a puppy has, and the people and animals it meets during this period, can have long-term effects. That’s why it’s so important to give the puppy pleasant, fun experiences with as many different kinds of people and situations as possible. If a puppy is properly socialized during the socialization period, it is much more apt to grow up to be a confident and calm adult that can deal with the social pressure and the environmental demands of a working dog. If a puppy spends the first few months of life in an environment that isolates it from the outside world it will not be well prepared socially or environmentally to become a working dog in the real world. Some learning will take place with dogs that have been restricted to one type of environment but not enough to allow it to interact or behave normally with new people, unfamiliar dogs and the sights and sounds that a variety of environments can provide. From a human perspective, it might be like experiencing a third world country for the first time only without the cognitive ability to understand what's going on around you.


All puppies, even littermates, develop differently and at different rates and will react to different stimuli with different levels of intensity. If a puppy is particularly sensitive and has a traumatic or very scary experience during its first few months of life, it can affect it for the rest of its life. For instance; a loud skateboarder rushing by or a car horn blowing in close proximity or being sprayed with a hose or attacked by another dog. Some puppies will recover quickly from these types of experiences while others may not recover at all depending on the dogs genetic make-up, breed, and temperament.


A handlers job is to keep the puppy safe and protect it from potentially threatening experiences during this period, while at the same time rewarding it for interacting with new people and things and showing bravery in the face of perceived foes in new environments.




Adolescence usually starts around 6 to 9 months of age and can continue until around age two years. As you may have already experienced, dogs tend to be impulsive and test boundaries during this very frustrating period. This is not a good time to be judging your dog for its occasional lack of interest in obeying your commands as they are very similar to a teenager during this stage of development. Although teenage dogs can be challenging, if kept them physically and mentally stimulated, they are much easier to deal with. I personally, find this to be very true.


Second Fear Period


Dogs go through a second fear period that lasts approximately three weeks and usually happens sometime between 6 and 15 months. As with the first fear imprint period, a single traumatic event during this time period is much more likely to have a long-lasting effect on the dog’s behavior than if the happened at other stages of development.


Dogs at this stage could suddenly become fearful of things they were previously comfortable with. Things like strangely dressed people or loud noises can be very scary for a dog in a fear period, be mindful during this period and try to avoid potentially traumatic situations.


Slow Down and Take Your Time


Think about how and what you are exposing your dog to during a critical developmental stage. If you find your dog is reacting to something it was previously not afraid of, don’t force the dog to confront whats scaring it. Go very slowly introducing unusual stimuli or scary looking objects during these periods and stay within your dog comfort zone. Use caution with just a few minutes of exposure for loud noises or novel experiences at a time. If your dog reacts badly to stimuli back off and keeps your dog under its fear threshold by providing some distance and a treat or toy distraction while you gradually work to desensitize it.


Remember, adulthood is just around the corner and all your careful attention and observations will pay off. A well-socialized dog is a pleasure to work with and will be able to remain calm and much less reactive or fearful in the toughest most distracting environments and may even save you a frustrating end to an otherwise great trail. Understanding your dog’s critical developmental stages may also save you numerous frustrating hours of trying to undo the damage caused by not recognizing developmental problems when they arise. All of us want quick results but sometimes our goals are not in line with a young dog's developmental stages and this can negatively impact your dog for a lifetime so try putting those lofty goals aside during critical developmental stages and proceed slowly, at your dog's pace.


References: Karen Pryor Dog Training Foundations Course (2014). www.karenpryoracademy.com.


By, Linda Porter


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