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Fear & Reactivity in Adolescence

Is your normally stable puppy suddenly freaking out at every little thing?   You've probably hit a normal adolescent fear imprint period.

OHMIGOSH!!  IT'S A ... fire hydrant.
Hair standing on end and hysterical at every little neighborhood noise,

high startle response, suspicion of strangers ... 


This is the age of awareness. Your dog suddenly notices that some people aren't part of the family, that there are strangers in the world. Puppyhood oblivion and acceptance of everyone as a potential friend is replaced with "are you safe?" and "do you belong here?" You may see them shy away from people in hats, wearing sun glasses, or some one carrying something. I often hear students exclaim,"He didn't recognize me!" Back-lit silhouettes are particularly alarming as the dog can't see your face. Someone entering a room unexpectedly may cause them to startle and bark.


See also: Developmental Stages

During the "flight instinct" period your puppy will experience periodic fear periods between 6-14 months. Adolescent dogs may spook at the silliest things. You walk down the same street every day for months and one day, out of the blue, he becomes hysterical at the sight of a fire hydrant that has always been there. Your pup may become unable to enter his own backyard because there's a wheel barrow parked in the corner that wasn't there before. Environmental contrast. They are on high alert when they perceive things aren't "normal."


The degree of startle response depends on breed and early socialization.
Dogs whose genetic heritage has programmed them to be alert and focused outward will often have an more pronounced fear period. Protection breeds (Shepherds, Rotts, Dobes) and herding breeds (collies, cattledogs, etc) will need increased positive socialization during adolescence. It's almost like one day they can see better at a distance. Suddenly they are noticing the neighbor across the street as he gets out of his car. Their alarm starts with a suspicious "boof - boof" followed by "bowrrrooooooo-roooo-rooo" going up in pitch. If this behavior is allowed to be practiced, their confidence in "scaring away the mail man" (he was leaving anyway) or neighborhood kids will increase. You don't want them to become experts in scaring the neighborhood. Continue positive socialization and training!


Between 6 & 18 months your dog is in adolescence. Becoming an adult. Living in an adult body with a puppy brain. Your dog experiences emerging territoriality and responsibility for the pack combined with conflicting feelings of puppy insecurity. Sometimes it looks like Jekyl & Hyde. While some breeds are naturally more vocal than others, the problem is magnified in dogs with limited socialization. Anti-social dogs become more so. Frightened dogs DO bite if cornered. If they find out that lunging and barking will make the scary thing go away, they will add it to their arsenal of behaviors that work. Control the environment so they don't feel they have to defend themselves. Do not encourage "watch dog" behavior at this age, you are rewarding fear and suspicion not bravery and confidence.


The more timid or unsure the dog feels, the more noise he makes. Young adolescent dogs pushed beyond their safety threshold frequently lunge and bark with hackles (the ridge of hair down the dog's shoulders and spine) raised. The more hackles, the more fearful the dog actually feels. This behavior is designed to create distance between them and the scary thing. Small breeds often bark more than their larger cousins - what they lack in size, they make up for in attitude and volume! Confident dogs make very little noise. Socialization is the key.


The good news is they do grow out of it  - with your support and guidance. It is important to continue to expose them to lots of new things. It may be easier to leave them home rather than take them on walks where a meltdown happens every block or so, but it's imperative to get them out in the world and carefully continue their socialization through gentle exposure to new things. 

From "Your Dog's Friend":


“Socialization” is not the same as exposure.

Socialization is an over-used term that has come to mean “throw your dog into any and all situations and hope for the best”. Your #1 priority should be to help your rescue dog feel safe.

  • Your dog’s experiences with other dogs, people and environments need to be good ones.

  • Dogs can develop anxieties from one bad incident.

  • Don’t force your dog into situations that make him uncomfortable.

Give your dog time to adjust. This is not the time to see family or attend public events.



Check out this great article by Debra Ekman of Your Dog's Friend: 
10 Tips for Humans



If your normally friendly dog suffers from a "sudden onset" of out of character behavior, there could be a medical reason. Thyroid imbalance or chronic pain, even allergies can cause dogs to behave out of their normal stable character. Do consult your veterinarian. If your dog is threatening to use his teeth, get professional help!


See also:

Suddenly Spooked -Secondary Fear Phase

Thresholds - Recognize & Respect Them
Growling & Barking - important communication

Treat & Retreat



This handout may be reprinted in its entirety for distribution free of charge and with full credit given:
© CAROL A. BYRNES "DIAMONDS IN THE RUFF" Training for Dogs & Their People -
ditr_training @ -



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