There are several reasons why your dog may dig, and not always because he is misbehaving.
Understanding your dog's behavior is the first step towards communicating with your dog and finding solutions for unacceptable behavior.
Many people purchase a puppy, toss him out in the yard, and expect him to behave. Puppies are like children - you need to spend time with them, teach them right from wrong, and reinforce good behavior with praise and treats. You should never hit a dog as this will only cause him to dislike you and may cause him to become aggressive.
There are several different reasons why a dog will dig. Dogs will dig to create a cool and comfortable spot to lay, particularly in warmer weather when it is hot in the open sun and the ground is very warm. The ground is cooler a few inches below the surface, so a dog may dig down to create a place to cool off. Also, if your dog doesn't have a soft place to lay, he may dig to mold the ground to fit his body, making a more comfortable resting area. It's not abnormal for a dog to dig several different pits around the yard - he'll want to be able to lay in the shade, so as the sun moves, he'll move to a different spot because it is cooler.
SOLUTION: Provide your dog with soft, cool bedding in a spot that's always shady. Or try making him a digging pit. It's much easier to teach a dog to dig in a certain spot than it is to teach him to stop digging all together.
Dogs will also dig if they smell or hear something underground, wanting to find the source. Maybe there's a small animal or insect burrowing, or something is buried underground - either way, this is simply “curious digging”. Breeds such as terriers and hounds that have been bred to hunt, track, and burrow after their prey are especially prone to this type of digging. It's not your dog's fault, but rather an instinctual urge they are exhibiting.
SOLUTION: Watch your dog when he's out in the yard. If you catch him digging a tunnel to the center of the earth, say "NO" and then give him something else to do. (Playing fetch, chewing on a toy, chasing you playfully, etc.) Occupying his mind and keeping him busy are the best solutions, plus it’s a good opportunity for you to bond further with your pet.
Another reason your dog may dig is because he is bored or lonely. If your dog spends large amounts of time alone - for example, if you work outside the home - and has little to occupy his time, it's almost guaranteed that he will turn his attention to 'irritating' habits like digging and barking. This is not your dog’s fault; those long lonely hours can really stretch out, especially for companionship-oriented animals like dogs, and he needs something to stimulate his mind and body. If your dog is left alone for long periods of time, he may be digging because he has nothing else to do, or he may suffer from separation anxiety. All dogs are pack animals, living in families. When you are away, your dog gets lonely and must be provided with plenty of toys to keep him occupied.
SOLUTION: Spend more time with your dog, and give him plenty of things to do while you're away. Giving him a different toy or bone each day when you leave may help. Exercising him regularly, including daily walks, may help tire him out and will allow him to get rid of all that excess energy he’s accumulated in an acceptable way. In some cases, having another doggie friend around can help, too. Talk to your veterinarian for more information on separation anxiety.
Dogs also dig as a natural way to keep their nails trim. Finally, some dogs just dig for fun, feeling like they could tunnel to the other end of the earth, and will not stop until they real their goal. Dogs like to have fun too, and this may seem like “fun” to them. For the stubborn dog who will not stop digging, you may just have to let him dig his hole, which he’ll eventually get tired of.
As a last resort, If your dog can't access the yard, he can't dig. If all else fails, and you REALLY don't want your dog to dig, you can restrict his access to the yard unless he's actively being supervised. This is a pretty harsh method, and it won't be much fun for the dog (or for you, especially when the primary reason most dogs dig is an excess of energy and not enough stimulation). Be cautious when deciding to restrict access to the yard, as taking away this outlet for releasing pent up energy, will cause your dog to be hyper; so be patient as this method is challengins, but it does work. Be prepared to compensate for his new, restricted life, you'll need to take him outside and play with him lots of times during the day. It will be a good idea to take your dog outside at least four or five times a day, for at least five to ten minutes each time. Also allow your dog some supervised time just to sniff around without being engaged in active play.
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