pitbull digging problem

Question
I have a 2 yr old female spayed pitbull mix terrier that is giving us a digging problem. shes been digging along the fence line to the neighbors house, they have 2 dogs that she seems to get along with, so im guessing she wants to go play. we have another dog but he's  a jack russel mix and doesn't interact with her much. my big concern is now she is digging toward a different neighbor who has a dog that seems aggressive toward my dog through the fence. I've tried chili powder, her own feces to no regard. I take her out at least 5 times a week to the park and play fetch till shes tired. im running out of options, is there anything else I can try? thank you in advance...

Answer
Dogs dig for many reasons but one strong predictor of this escape behavior is boredom.  Digging can also be related to prey drive (which may have been the original cause). Since your dog has developed this problem, it's obvious she should NOT be left unsupervised outdoors.  If the dog is confined outdoors for long periods and without observation, she's going to continue this behavior no matter what you do.  Since escape poses the real risk of death (from cars), injury or outright loss, it makes no sense to perpetuate a situation that is obviously posing these risks.

Taking a dog out five times a week to play fetch doesn't do a thing for the dog.  Social interaction with family members on a daily basis is the entire purpose of having a dog.  A dog that is socially isolated is going to get into all sorts of trouble; such a dog becomes very anxious, also, since social isolation is extremely punishing.  If you're leaving your dog outdoors alone when you go out of the house, you'll have to determine a safer, humane way to confine her indoors (such as the kitchen).  Working with a dog using positive reinforcement training engages the dog's mind as well as capturing behaviors that can be rewarded; this can be done in short sessions (five to ten minutes) a few times a day.  If the dog's quality of life is increased and her sense of affiliation becomes stronger, the need to dig out should diminish BUT it may have become habitual which means you need to be especially vigilant.  Do NOT leave this dog outdoors alone.

There are fence materials designed specifically to create safe barriers (for those without a fence) but which can offer an additional perimeter if placed a foot or so inside the existing fence.  There are also humane water sprayers which trigger when motion is detected and spray the dog in an attempt to create a startle effect which results in avoidance of those areas.  Here are links to both products:
http://www.bestfriendfence.com/default.asp
http://www.amazon.com/dp/B000BO71NY/?tag=googhydr-20&hvadid=3870435321&ref=pd_sl...

Remember that your dog does not know/understand the extreme danger of digging out of her yard.  Not only can she get into trouble with a neighbor's unfriendly dog or get lost or injured/killed, but a dog at large poses a risk to drivers, young children, elderly, etc., and you become directly legally responsible should such an event occur.  For the dog's protection, a re-evaluation of why she's out there in the yard long enough to engage in digging behavior must be done.