Aggressive behavior in aussies

Question
Hi Matt,

We have an Aussie that we rescued from the local humane soceity last October.  (He is about 4 years old and you can see a picture of him on my web page... http://webpages.charter.net/bobbridges)

He is pretty "normal" when we compare him to all we have read about aussies... very loyal and protective of owners and property, wary of strangers,etc...  He was pretty quiet and low key for a while after we brought him home, but has grown out of that!

Here's the issue... While he has never shown any aggression toward my wife or me (no kids), he still wants to herd and is pretty aggressive towards other people (even friends who have been to the house several times.)  He has never bitten anyone, but a couple of weeks ago he went after a friend (he lunged at her and "bumped" her with his snout... he could easily have bitten her, but all he did was "bump" her and then immediately backed off.)  

We have taken him through basic obedience training and he did well with that.

Any ideas would be appreciated!

PS... he has started licking metal for some reason... any ideas there?  (We notice this mostly when he licks his kennel and the metal part of the back sliding-glass door.)  

Answer
Agressiveness is very common in aussies, as you have read. Some lines are stronger than others. If someone is down on the floor he is more likely to snap. What he is doing is herding, and this is a herding dog. There isn't much you can do about it, but next time he does it say no very loudly, and put him by himself in a room, but not in his crate otherwise he will look a his crate as a bad place. If you are consister, aussie want to please their masters so he should get the picture that he shouldn't do that.

About the metal, my Indie does the same thing. There be something they find "tasty" on it, just part of the metal. I don't think it will hurt him, but if it bothers you then I would get bitter apple spray and he will stop. I hope this helped! Email me back if you need to know anything else. P.S. You aussie is adorable!!!