German Shepherd Adolescence: When the Guarding Arrives (Six Months to Three Years)

Somewhere around six to eight months, the German Shepherd who greeted everyone starts to watch them instead. The recall wobbles, the energy doubles, and one day a stranger at the door gets a bark that surprises you both. This is adolescence, and in Shepherds it comes with the arrival of the guarding instinct. It is normal, it is temporary, and it is the period that decides what kind of adult you get. Most settle between two and three.

What's happening

Hormones, a brain rewiring itself, a body that can now outrun you, and the breed's natural wariness switching on. The dog hasn't forgotten the training; the world has become both more interesting and more suspicious. Fear periods come and go: a dog who was fine with the bin lorry is suddenly not, for a fortnight.

What to do

• Long line, everywhere the recall isn't perfect. A seatbelt, not a punishment. Reward every recall like it's the first.
• Keep socialising. Calmly, at a distance, every week. The puppy work is what the adolescent leans on. Most owners stop here because it got harder; that is exactly when to keep going.
• A job every day. Scent work, tracking, obedience games, tug with rules. A bored adolescent Shepherd invents a job, and it is usually guarding the window.
• Manage the door and the window. A mat routine for visitors, film on the glass, a gate in the hall. Every rehearsal of barking at the postman makes the next one louder.
• Go back a step in every skill and pay better.
• Consistent rules across the whole family. Teenagers test edges and find the soft one.
• Protect sleep. Fourteen to sixteen hours, and they often won't take it unless you make it happen.

The first growl

At some point an adolescent Shepherd growls at something: a stranger, a dog, a hand near the bowl. Don't punish it. A growl is information, and punishing it teaches the dog to skip the warning next time. Add distance, work out what worried them, and get a force-free trainer in early if it happens more than once. Early help is cheap. A reactive three-year-old Shepherd is not.

What not to do

Don't punish the recall when they finally come. Don't add hours of running to burn it off; you build stamina, not calm. Don't 'show them who's boss'; pressure makes a wary dog sharper, and a sharp forty-kilo dog is a danger. And don't neuter to fix it: little evidence it helps behaviour, evidence it can affect joints, and in this breed some evidence it can make fearful dogs more fearful. Talk timing through with your vet.

When it ends

Usually gradually, between two and three, you notice the dog you trained is back, steadier, and watching the world with judgement rather than alarm. Everything you did during the difficult months is what that dog is made of. Hang on. For the specific problem of barking and lunging, the reactivity guide is the next read.