If your puppy is barking at you and biting, it doesn't mean he doesn't love you. This can be normal behavior, depending on the situation and duration. If the behavior has been going on for days or weeks, there's probably a specific problem that goes beyond wanting a certain toy or reacting to a one-time issue.
Understanding the reasons puppies bark and bite will help you try to determine the cause, then come up with the correct solution for dealing with the problem. Dogs that bark a lot may be doing so for a number of reasons.
It’s just rough play
Puppies don't have enough experience with humans and other animals to know when rough is too rough, explains Best Friends Veterinary Center. This problem can become exacerbated when an owner encourages roughhousing, such as playing tug-of-war with a toy or wrestling with the puppy.
Look to see if the puppy's tail is wagging during its barking/biting episodes and if he is quick to snuggle or lick you after your play session has ended. If the puppy's ears are pinned back, he's baring his teeth or lowering his tail, the aggression is probably more serious, according to Best Friends.
The puppy has physical pain
In a 4-month old puppy, aggressive biting or barking or otherwise acting out of character might have physical pain. It could be teething, a thorn in its paw, fleas it can't scratch, or an internal medical problem. If the dog can't get relief, its barking and biting might be an attempt to get your attention. Try to look for patterns in the dog's behavior regarding when the barking and biting starts.
If it occurs each time you turn on the TV or start the dishwasher, that might be the cause. A dog might get aggressive if it's "protecting" its water or food bowl, bed, or toy — and toys aren't limited to items you give them. They might attach to a particular pillow or other object and claim it. If the barking and biting occurs randomly, you might need to contact your vet to see if there's a health issue you're not aware of.
The dog is afraid
Whether a dog is just startled by a noise you've made or has an ongoing fear of something, it's a common reason for puppies to bark and bite, according to the American Kennel Club. This is especially understandable if you have recently brought the puppy home. Until it explores the house and learns what is scary and what isn't, it might continue to act defensively.
Make sure that you pick a spot for your puppy's bed and water and food bowls and avoid moving them. While you might think it's OK to experiment with different places for a dog's things until you find the right spot, dogs like and need routines — moving their items confuses and upsets them. This might not cause them to bark and bite, but they are now primed and ready to overreact to other triggers.
Dealing with the behavior
The first step to ending this behavior is to identify what's causing it. This might take several instances of watching when the barking and biting starts to determine what repeated event is causing the dog to react this way. If you find the issue, such as a clock or appliance upsetting the dog, hold the dog while you start the appliance or while it's running, then touch it, showing the dog the item is not a threat.
You can also do this while the dog is across the room and you're next to and touching the object. Aggression can also come from a dog being tired, or not getting enough exercise and becoming "wound up." There are also some dogs that bark a lot, plain and simple.
Don't punish an aggressive puppy by yelling or swatting it, advises the AKC. This will only confuse the dog. If you can reward the dog with treats and hugs when it stops its barking and biting, this positive reinforcement will help. If you can't identify the reason for the dog's behavior, it might be time to call your vet, professional pet sitter, or dog trainer. The sooner you deal with the problem in a puppy, the less chance there is in it becoming a long-term problem.