Ive had thoughts about why dogs bark? Just because they bark doesnt mean their aggressive. I am researching this now. What causes me to ponder is that I was pet sitting 2 collies for someone who had collies and 3 pit bull mixes at the home; not housed together; but in different areas of the property. Now like most people, I am not comfortable around pit bulls because of their reputation.
One of the collies walked up to one of the pits that was barking from his crate and stuck his nose through the crate at the pit. The pit backed up and kept barking. I thought the collie would lose part of his nose, but it didnt happen. I thought how curious. There was another pit gated in the kitchen area. She was barking, holding her left paw up, and wagging her tail, ears down, while backing away from me. I took them both to be non aggressive.
I was not responsible for the pits only the collies, but i was in the house by myself, so there was a bit of a stress factor going on. I had gotten there before the owners; so the pits had not been up in anticipation of my arrival.
When the owners came home, the dogs were told to be quiet and they were. When I asked them to be quiet, they kept on barking. I surmised they dont know me, so therefore they barked to keep me back. There was no growling. Needless to say, I respected their wishes. I am sure I looked ridiculous holding a tennis racket in front of myself (one of Cesar Millans tactics) claiming my space when the owners walked. Never mind, it worked.
Back to the collie. He did not seem afraid of the barking, only curious. So, whatever communication coming from the pits it was not to insight fear to us, but to just back off, which the collie and I both did. I have seen this particular collie fearful ; he was not displaying that at all.
More to learn....