Small Changes Can Help So Much
Many time resource guarding type behaviors can be avoided if we respect the dog's space, don't tease or stick hands in bowls or their food, or otherwise harass them when they are eating or with a chew.
Often times, resource guarding occurs because of the dog’s perception of an event. It can happen even if the human doesn’t think the thing should be that important or if it doesn’t make sense to the human. If the dog feels it, it is so. Perception is often the reality.
Of course, if you think your dog might be showing resource guarding behaviors, address them with a professional as soon as possible. Oftentimes, this behavior can spread like wildfire. There can be many reasons why the dog is showing those behaviors. The longer it goes on, the worse it spreads. Choose someone who has a deep level of canine education.

