barking and nipping

Question
I have a 4 month gsd and he will on occasion just stand and start barking at us and nipping.  What can be the reason and is there any humane way to stop this behavior?  I really want my puppy to be a member of our family in all ways..so would appreciate your help..
thanks

Answer
It sounds like a way to get attention.  You need to combine never rewarding it with attention with giving him more attention when he is quiet.  Turn your back on him, walk away, but never pet him.  

Young Labs, which I know best, and other puppies tend to very bad about biting. You see a litter of them, and all the ones that are awake are biting another one or themselves. I am not even sure they realize that when they are alone, if they quit biting, they would quit being bitten. At 3 to 4 months they are getting their adult teeth, and it seems they spend every waking moment biting or chewing. One thing you can do at that stage is to knot and wet a piece of cloth. Then freeze it. The cooling will soothe the gums. Only let the puppy have it when you are there to watch it. I maintain a Lab's favorite chew toy is another Lab. Otherwise they settle for any person they can. They keep hoping to find one that won't yelp, jerk their hand away, and leave.

You just have to keep on correcting them, hundreds of times, not dozens. Provide sturdy, safe toys such as Kongs and Nylabones. Avoid things they can chew pieces off and choke on them. Keep them away from electrical cords. Crates are essential for most young Labs and other dogs.