Note: If your dog is displaying signs of aggression around food or toys, I recommend you contact a trusted trainer in your area.
Dr. Patricia McConnell had a great post on her blog “The Other End of the Leash” last week about how to deal with a dog’s possessiveness using desensitization and classical conditioning. It’s worth reading if you have a dog with possessive aggression of food, toys, space or whatever it might be. Instead of teaching the dog “drop” or “leave it,” (which I highly recommend you still do), you are conditioning the dog’s response to someone approaching the object of value.
The basic idea McConnell describes is to find something your dog likes even more than the object she guards. So, maybe your dog guards rawhides, but she likes pieces of hot dogs even more. What you would do is set up a scenario where the dog is likely to guard a rawhide. With your hot dog bits in hand, you would then walk up to your dog but stop well before she starts to guard the rawhide. Toss her a piece of hotdog and walk away.
You want the dog to think, “No! Don’t walk away!” McConnell wrote. Then, very gradually, you decrease the distance over several short sessions over several days until your dog is OK with you approaching her while she has a rawhide. Then you also need to condition the dog’s response to someone reaching for the object. You would do this by bending down near the dog, dropping a hot dog bit and standing back up. Eventually, you will move your hand closer and closer until you can safely remove the object and give the dog something even better in return.
You are not training your dog to respond to a cue, McConnell wrote. You are conditioning an internal response to someone approaching something the dog cherishes.
This is certainly not the only way to deal with a dog’s resource guarding, but I like the approach and thought many others would find it helpful.