Sudden aggression seems, to Harry’s owners, to come from nowhere. They took the German Shepherd on in good faith five years ago, at the age of two, little knowing what they had let themselves into.

The couple are experienced German Shepherd owners and have stuck with it.

Sudden aggression

Harry and George

The other day, seemingly with no provocation at all. The lady was by herself and both dogs were asleep on the floor.

With no warning, Harry suddenly attacked their other Shepherd, Bomber.

He grabbed the younger dog’s neck and shook him violently.

The poor lady sat and cried

This was not the first time Harry has suddenly attacked Bomber, but it was the worst. The lady screamed. She so upset that she just sat and cried. They couple wondered whether they can live with his sudden aggression anymore.

Taking on a German Shepherd like Harry isn’t for the faint-hearted. In the crucial early months when he should have had plenty of positive experiences involving humans, he has probably suffered either unpleasant experiences or neglect.

Judging by the condition he was in when they homed him, in my opinion he may well have been used as a guard dog – left outside by himself in a yard. It has to be guesswork, but I have met ex-guard dogs with similar behaviours.

Each time he hears anything outside he barks. When he hears the neighbours he goes frantic. If someone crunches up the drive to the door he goes mental. This is when he may well redirect onto poor Bandit.

Each time there is an incident that causes Harry to become over-aroused, the adrenal and thyroid glands, testosterone and hypothalamus begin to increase their production. The output from these glands not only reach a peak 10-15 minutes after the incident but can remain in his system for hours – days even.

With poor Harry, the ‘incidents’ are simply too frequent. He has to find relief somehow. Grabbing something and shaking it is one way. It could be a ball or it could be sudden aggression directed on poor Bandit.

Explosions of sudden aggression.

Due to his inner state and build-up of stress, there will be times when it takes the smallest thing to tip him over the edge. It could even be the neighbour’s car door shutting -inaudible to the humans.

The only way we can approach this is by working on the emotions which are causing the behaviour. By helping him.

They will do all they can to reduce his constant hyper-vigilance. First they will determine as many areas as they can that cause the dog arousal/anger and endeavour to reduce them. They will do this in two ways.


One is to remove as much exposure as possible. They will block Harry’s view out of the front windows. They will keep the gate locked and move the mailbox beside it. They will put a doorbell on the gatepost.

They can have a second bell push and work on habituating him to this door bell so he no longer reacts when he hears it.

Changing how he feels

Very importantly, when he does bark on hearing something outside, they will work on changing how Harry actually feels by how they react to his barking.

If he can be much calmer in general, it stands to reason that this will make his explosions of sudden aggression a lot less likely.

‘Operation Calm’ is therefore where we need to start.

After all these years of working around Harry’s problems and changing their lives to fit, they deserve a bit of a break. They are constantly on their toes.

NB. For the sake of the story and for confidentiality also, this isn’t a complete report. If you listen to ‘other people’ or find instructions on the internet or TV that are not tailored to your own dog, you can do more harm than good. Click here for help