Rescue Chi in Defensive Mode

Aggression is a major reason why dogs are surrendered to rescue organizations and humane societies, who then must decide what to do with the pooch.
A Chihuahua named Loco is one of those dogs. His rescue people decided to work with him, to make him safe and adoptable, and asked for my advice. I thought it perfect blog post fodder.
Watch this video Loco's foster parent made:
https://www.youtube.com/watch?feature=player_embedded&v=AKM1lr1JjXI 
Loco is described as guarding his crate, and although he reportedly also guards food and toys, I’d say that he is defending the safety the crate represents, rather than possessively guarding the object. He doesn’t want people near him because he doesn’t trust them.
How trainers work with a dog like Loco depends on their philosophy and skill level. Any of the things below are done to dogs – it all depends in whose hands they are lucky, or unlucky, enough to fall in.

1. Euthanasia. Nowadays, thanks to the popular No-Kill movement, fewer aggressive dogs are killed and more get a second chance.

2. Hands-on force.
Toys are easy to overpower, so why not put on heavy leather gloves and forcefully take Loco's resource away until he understands that all things belong to people and stops objecting?
Couldn’t we just pin him until he submits?
Although we don’t know for sure, chances are that it is exactly that kind of treatment that caused Loco’s aggression in the first place. A dog forced and overpowered doesn’t get used to being manhandled and losing his valuables, but becomes increasingly more suspicious and defensive. If he only succeeded once with the aggressive displays and the person he felt threatened by backed off, aggression was powerfully reinforced and became his default mechanism for keeping people away.

3. One could use a shock collar and zap the expressions out of him.
Shock collars, banned in some countries, are commonly used in North America. There are, in fact, shock collar franchises. Why are they popular? Because they can be effective. A shock impresses the dog and often suppresses the undesired expressions pretty much right away. That impresses the owners: they don’t see how their dog feels anymore and are happy. It's a lucrative business. But make no mistake: the underlying emotion does not magically vanish. How anybody believes that a shock makes a dog feel better about people, dogs, or whatever the triggers are, is delusional.
If you can stomach watching shock-trained dog video clips, you see robotic, mechanical obedience and behavior: dogs that won’t do anything but what they’re told, and are eerily non-responsive regardless what situation they're put in. No behaviors offered; dog’s spirit left the building.

4. Rewarding the dog for appropriate, friendlier behavior.
That is a more humane approach, popular with force-free trainers, and the one the foster home chose with Loco. The reward is distance, so moving away, as soon as the dog stops his aggressive displays. You see that clearly in the clip. The concept behind it is that if you functionally reinforce the desired behavior, the dog will do more of it, and in time become friendlier and more trusting because people don’t steal and hurt anymore. It sounds logical, but is not how I work with aggressive dogs and here is why: What is happening here, in operant conditioning terms, is negative reinforcement: something unpleasant is applied, and when the dog shows the behavior we are after the pressure is released. The problem is that the person is still “something unpleasant”, which means we might be changing the dog’s expressions by reinforcing the more preferable ones, but we are not changing how the dog feels about people any time soon, and as long as people put pressure on the dog. Humans, from Loco’s point of view, are still bad news, and the only thing he learns is to do certain things to make them go away. I'll elaborate in my next post why I don't like manipulation of communication and body signals.
In addition Loco was clearly overwhelmed with that exercise and "practiced" aggression for a period of time before he finally walked away. It is not a conscious process, but brain pathways are strengthened every time neurons fire. Behaviors that are well established, that are done over and over again, have very strong neural pathways. When we work with dogs, we want to do everything possible not to strengthen the aggressive pathways further.
There are some real physiological things happening when a dog is anxious, afraid or angry. Adrenalin level rises, and when that happens a lot a dog can become chronically hormone imbalanced, and we want to avoid that too.

5. My goal, when I work with a defensive dog, is to change his emotional response to the trigger: from it being perceived as potential trouble to it announcing something wonderful. If done successfully, the nasty expressions will simply, authentically, disappear.
This is what I wrote Loco's foster person: Think away from operant conditioning - what, or what not, you are reinforcing. Don’t see the aggressive expressions as negative behavior that needs to be quelled, but the emotional state the dog is in. We might not like it, but he can’t help it.
To instill trust in people, walk toward the crate, toss Loco the best treat, and walk away. Treat and retreat, without any strings attached. He gets it just because a person is approaching. No pressure: You don’t hang around the crate, you don't look at him, and there is no demand for him to do a certain thing.
Most dogs quickly begin to anticipate the appearance of the trigger, in Loco’s case the human, excitedly because they associate it with something good.
Once Loco begins to trust, the person gradually gets closer and stays close for longer, and looks at him for longer. The next step is expanding, using the same approach, to all problem zones, and then incorporating different people.
You want to orchestrate many opportunities for Loco to experience that humans are, with 100% predictability, non-threatening. Emotional safety cancels the need to act defensively, but safety has to be felt: it can neither be taught with reason, nor forced with compulsion.

The wonderful people who are working with Loco are giving this try and promised to keep me in loop. I will update you.