Hi everyone. Today my dog showed a very strange reaction. We were hiking, us going up the mountain, and some guy was coming down the mountain - the second my dog saw the guy he hackled up, stood hi on his toes and started growling, deep throaty growl. The guy wasn't even very close when this occurred. I corrected him and put him in a down stay. He kept the down stay and the guy was able to pass him within inches (narrow trail) with no problem. But I believe my dog would have gone for the guy if left to his own instinct.

Hiking is not foreign to my dog. We've been taking him camping and hiking since we got him a year ago. He's now 17 months old. Neutered at about 14 weeks of age at the pound. 80 pound shep x. Up until this incident he's not shown inappropriate aggression (IMO). Other instances of aggression, that I found acceptable: 1) ranger entering into our campsite, dog growling and barking, stopped when told, ranger was able to approach and pet dog. 2) Some stoopid lady entered our driveway uninvited because she wanted to pet my cat. Dog growled and barked at her. stopped when told to stop. Did not want the stoopid lady to make friends with my dog. 3) Some guy ignored the "beware of dog" sign and came in the yard. Dog cornered the guy and was barking at him. (dog was young. 8 months old I think? Totally insecure display. I believe the dog could have been chased off if the guy was acting confident. gave us a good laugh tho.)

I feel my dog is well socialized. I walk him and do OB regularly with him in an area where there are people jogging by. Joggers have jumped over him while he's in a down stay and it doesn't phase him. Toddling kids have fallen on him and all he does is lick them. My work takes me into downtown SanDiego and I take him regularly so he's used to all sorts of noise and crowd. Been to parades. Spent a week at Yosemite in June. Just came back from a week RVing to the Grand Canyon. This dog's no shut-in.

The hiking incident - there were people of all shapes and sizes jogging and hiking past us. He didn't react to anyone else. I really can't think of anything odd about the person he growled at. He's a doofy friendly dog. People who know him can't believe my description of what he did.

Anyone have any insight????

Those things are hard to call, especially after the fact. Think how different the dog's physical perspective is from yours. It can be hard for us to understand what he's actually seeing, let alone what the guy might have smelled like, or subtly signaled to your dog.

I mean, think about from the dog's viewpoint, lower to the ground looking up, and looking up a trail, could he have been looking at a black blob against the sunlight? Something like that we might not see because the view and elevation are different for us.

One of my dobes had cataracts and would go ballistic at club when people crossed in front of the very large, bright windows -- even people he knew. The light dispersion really distorted what he saw. When the windows were dark, it didn't bother him at all.

Also hard telling what the dog might be smelling. There's just no way for us to know where that guys shoes had been.

An acquaintance of mine works in a slaughterhouse. I don't smell anything on him, but something with him really gets the dogs going. He doesn't have bad body language, and they settle right down, but the combination of chemicals, offal and whatever must linger enough to interest/weird them.

Good luck figuring it out. I'd guess he was just growing up, except you said it was only that one guy.