I’ve written about socialization before, but it’s been a while: I haven’t raised a puppy since Game was little. And she’s turning 5 this year! It’s hard to believe how time flies.

I’m not going back to see what I wrote when I raised Phoebe, Hadley, Grit, and Game. I’m sure my opinion about socialization has changed since then – it’s constantly evolving as I/we dog trainers learn new things.

The sensitive socialization period

I’ll define socialization as introducing a puppy to the stimuli they will encounter in their adult life. Ideally, this introduction will happen during their sensitive socialization period. It is currently believed that the sensitive period lasts from 4 weeks (the age when puppies first leave their nests; Scott & Fuller¹) to approximately 3 months. The most important part of the socialization period, says Jessica Hekman², happens before the age of 8 weeks. During the socialization period, the puppy’s brain learns what stimuli are stressors, how much stress hormones should be released in response to these stimuli, and how long the stress response should last.

While dogs can still learn to tolerate or even like new things later in life, one of the reasons the socialization period is so important is that puppies are much better at generalizing at this age: meet one or two friendly small dogs? Deduct that all small dogs are friendly! Meet one dark-faced, pointy-eared dog – assume that all pointy-eared, dark-faced dogs are friendly. If they met the same kinds of dogs for the first time later in life, they might, in contrast, learn that this particular dark-faced, pointy-eared dog is friendly, but all other dark-faced, pointy-eared dogs are potentially still evil spawns.

I love Jessica Hekman’s image for the socialization period being the time when the on-switch (what turns the stress response on?), volume setting (how intense is the stress response going to be – i.e. what amount of stress hormones will be released?) and off-switch (when should the stress response end/how quickly should the dog recover from the experience) are being set.¹

Interestingly, at a very early age – the so-called stress hyper-responsive period – , animals don’t show a stress response at all. Their brains do not yet make stress hormones in response to scary stimuli! That’s another reason early socialization is crucial: puppies show no fear response to scary stimuli before 5-7 weeks of age. Therefore, a puppy that just left the nest around 4 weeks of age is MUCH more likely to form positive rather than negative associations to the people, dogs, and objects they encounter.¹ Once the puppy is 7 weeks old, making positive associations to new stimuli becomes significantly harder: suddenly, cortisol is part of the picture!

Genetics

When the fear response first appears varies between breeds. For example, German Shepherds start experiencing fear around 5 weeks of age. Cavalier King Charles Spaniels only start experiencing fear around 7 weeks of age.³ Cavaliers, then, have 2 weeks more time to learn that the things, people, and animals in their environment are perfectly safe – which may be part of the reason Cavaliers tend to grow up to be open and curious towards new people, dogs, and objects, whereas German Shepherds are, generally speaking, more reserved. A lot can be learned in 2 additional weeks of fearlessness! This shows us that genetics are part of the equation, too. The puppy you get at 8 weeks is not a blank slate – it never was a blank slate to begin with, not even in utero.

My approach

Let’s veer away from the science for now, and look at socialization in practice. The trainer I am today approaches socialization pretty relaxedly. In contrast, the trainer I used to be recommended clients with new puppies go through a list based on Ian Dunbar’s recommendations:⁴ X number of new people feeding their puppy treats every week, X number of weekly new dog encounters, etc. I even had a handout my clients could check boxes off on, based on Ian Dunbar’ socialization list⁵. Dunbar recommends puppies meet 100 new people in 4 weeks. I lowered the number because I didn’t want to overwhelm my clients before they even got started, but it must still have been stressful for them to see all the experiences they were supposed to provide for their puppies.

High-confidence puppies

Now, I just play it by ear. An open, outgoing puppy (like Game was) – I’ll just hang out around stimulating situations with them, at a distance they are able to contain their excitement. I’ll let them watch. I’ll play a little if they are ready. I’ll let them watch some more. With a socially confident puppy, I’ll focus on relaxation and engagement with me in the presence of distractions rather than actively having them meet stimuli they are already eager to approach.

Fearful puppies

With a fearful puppy, on the other hand, I want to do more than just generate neutral experiences. I want them to have distinctly positive experiences with the people, dogs or objects they are unsure of. To the best of my abilities, I’ll curate these encounters to build a library of positive experiences in the puppy’s brain.

Shy and “dominant” puppies (don’t lynch me for using the D-word, folks)

With an overly (for lack of a better word) dog-dominant puppy, like Grit was, I’ll try and arrange playdates with dogs who will – gently, but firmly – put them in their place if they cross certain boundaries. Lukas Pratschker’s Malinois was a great help with this when Grit was a puppy. My Greyhound Fanta knew just when to intervene, too.

With a dog-shy puppy, I’ll do the exact opposite, and introduce them to the calmest, friendliest dogs available to me. Again, Fanta was the perfect fit. For play dates, I might stick to puppies who are smaller and younger than my own puppy in order to give them a bit of an advantage and up their relative confidence.

With a people-shy puppy, I’ll work on growing their circle of human friends, and at the same time never force an interaction (this is something I learned over the last few years: by the time Grit was a small puppy, I still used to force things). Today, I firmly believe that whether to interact or not should be the shy puppy’s choice. My role as their handler is to make it as likely as possible that they will choose to approach voluntarily. At the same time, whether working with people or dogs, I’ll make sure the puppy has a safe place to retreat to (such as a crate, my body to hide behind, or my arms – they can always ask to be picked up).

So far, so good – that’s my art and science of puppy socialization in a nutshell. In the next post, we’ll look at what I did with one individual – puppy Puzzle – in practice!

Sources:

(1) Jessica Hekman – The Biology of Socalization (Webinar at Fenzi Dog Sports Academy, January 27, 2022)

(2) Scott, John Paul and John L. Fuller. Genetics and the Social Behavior of the Dog. Chicago & London: University of Chicago Press, 1974.

(3) Morrow et. al. “Breed-Dependent Differences in the Onset of Fear-Related Avoidance Behavior in Puppies.” Journal of Veterinary Behavior Clinical Applications and Research 10(4), March 2015. DOI: 10.1016/j.jveb.2015.03.002. (Thank you for poointing out this study, Jessica!)

(4) Dunbar, Ian. AFTER You Get Your Puppy. Berkeley: James & Kenneth Publishers, 2001.

(5) Dunbar, Ian. Socialization Log. (PDF)