Why do dogs growl?
1) Fear – dogs which are not used to strangers and want them to back off or are in an unfamiliar place may become fearful and growl to express this fear. Best to have the stranger back away or leave the dog along for a bit to let it get accustomed to the environment.
2) Resource guarding – dogs can become possessive of objects or locations they think are theirs. A dog may growl if they think their space is being infringed upon, or that you will take their bone, toy, or food. Resource guarding can usually be worked with and this is a good indicator that should get some help modifying his behavior.
3) Pain – dogs which are injured are prone to growl when they are hurt if they sense someone is going to agitate the pain they have. They are also likely to be confused as to what is going on and what is causing the pain.
If your dog growls, or you are in a situation where a dog growls, be thankful for the warning and see what you can do to deescalate the situation.
Let us know what situations you have had with growling.