Pet Health Pictures Slideshow: Top 12 Behavioral Problems in Dogs

Dogs like to dig, and you'll need to train them to get them to stop. You need to catch your dog in the act to stop digging. Say "no" and distract him with a toy. Scolding him after he's already dug a hole doesn't work -- this is all about being consistent when they're digging, not afterward. Tip: Give him a sandbox where he can dig. Then bury some favorite toys and watch him have fun digging them out.

Dogs, especially puppies, explore the world with their mouth. They like to chew because it calms them. But it's destructive and could lead to them eating things that they shouldn't -- like socks that could block their intestines. Break this habit right away. Give your dog chew toys, and give them to him when he chews things he shouldn't.

You can prevent this by never giving your dog food from the table. If you don't give him table scraps, he won't learn to beg. You can take him out of the room while you eat or put him in his crate. Or teach him to go to a special spot while you eat.

Always praise your dog when she comes to you, whether called or not. That way she learns that coming to you is good. If she doesn't come, don't chase her. Call her again while moving away. If she still doesn't come, tell her to sit, and go get her. Running from her may make her come after you! Say "come" or "here." She may not understand what you want if you just call her name.

Help your dog learn to walk calmly beside you. Never let him pull. Or else he'll learn pulling sometimes pays off. Keep the leash short but loose. Stop whenever you feel it go tight. He'll stop to see why you aren't moving. When he comes back, reward him and keep walking. After a few days, your dog will learn that pulling gets him nowhere.

If your dog gets upset when you leave, teach him that you'll always come back. At first, leave him alone for just 5 or 10 minutes. Stay away a little longer each time. Give him a chew toy and leave on the radio or TV. Be calm when you go and return so he knows that being alone is OK. Crate-training your dog can prevent separation anxiety. However, it can be trickier to crate train an anxious older dog. Ask your vet for advice.

Does your dog whine? If you pet her, look at her, or do anything except ignore her, you teach her that whining works. To stop it, turn your back when she whines, fold your arms and look away, or leave the room. Pet and play with her when she's not whining.

To cut the barking, teach your dog a new habit. Pick a spot within sight of the door. Then teach him to lie down, and stay when you say, "Go to your spot." That will help your dog stay calm and give him something to do while he waits to be greeted. Have a friend with a treat come to the door, but only open it when your dog’s quiet. Do this enough and he’ll learn to be quiet to get the treat.

It’s natural for a dog to greet people by jumping up. But that can scare away guests! Don't give your dog attention unless he has his front paws on the ground. Then you can greet him and pet him. Or tell him to sit. Then wait until he does before petting him. It also helps to keep your greetings low key. That helps your dog learn to control his own excitement. Also, make sure you keep your dog from bothering or scaring people who aren't used to him.

Any dog can bite if she feels threatened or nervous. But socializing a dog early teaches her to feel relaxed around people. Gradually expose her to different settings so she will feel safe. Spend lots of time with her so she learns to trust people. Always watch for signs that your dog is uncomfortable and then do what you can to make her feel better. Be especially careful around kids and food.

When dogs are aggressive, it's usually because they're afraid or nervous. If your dog is aggressive, work with a professional trainer or your vet to learn how to teach your dog to rely on you in a healthy way. Never leave an aggressive dog alone with children or unfamiliar adults, even if you think he's not likely to hurt anyone. Muzzle him in public places, if necessary.

Some dogs bark at things most dogs ignore. Some bark when they're frustrated. Don't yell at your dog when she barks. That may make it worse. Obedience training can help fix frustration barking. If your dog learns to sit before doing something fun like going for a walk, she learns to control her impulses. If your dog is outside all day, changing that may help compulsive barking. But you may need to work with a vet or a trainer.