He is supposed to bark, that's a good thing. He is warning others to stay away. We used to have a male Pyr that would bark all night long and when it would get on our nerves too bad, we'd just open the window and yell at him and he'd stop for a good while. Our female ONLY barks if there is something near, and our new male doesn't bark too much either, a little more than her but not bad, mostly only if he hears or sees something out of the ordinary. I LOVE my Great Pyrenees. Wouldn't trade them for anything in the world. They are my babies and are SO good with our kids.