I cannot speak on behalf of ALL dogs but I can tell you our dogs' reasons for digging. All legitimate reasons if you ask them.
1. To bury something
Our guys never tried to bury food items outside. In fact, Jasmine was the only one who would bury things.
Frequently, on our walks, she'd find various treasures. Mostly gloves, sometimes other things depending on the place and season. She took it as her duty to take care of these treasures and put them where they belong - underground.
She was very meticulous about it. Not any spot would do. There were times she'd start burying an item and then change her mind and went looking for a new spot. It would take her on average at least half an hour to find just the perfect location.
She also kept a list of all the items and when there was an opportunity she'd check on them to make sure they are still good and safe. When they weren't, she'd dig them out and find a new place.
It was one of her regular activities during our walks and and the friends' farm. There it was a daily job, because they aren't very careful about their gloves and leave them laying around haphazardly. So many gloves to be taken care of, so little time ...
2. To dig something out
Other than Jasmine's maintenance of her treasures, digging something out—namely mice and other little critters, is Cookie's specialty, though JD is taking a lead from her lately.
Cookie typically has little success with this endeavour, but it is not for lack of trying.
She actually does catch mice quite regularly but when they come out, not by digging down to their hiding spot. That doesn't slow Cookie down, though. Just on our last outing of the day, she saw a mouse dash for cover in its hole. She then spent almost an hour trying to dig her way to it.
Cookie is very determined with this too. She'll keep digging until she gets what she's after or has to go home. So far she's always had to go home; poor girl.
3. To make a cool spot to rest
All of our dogs, with exception of Bruin would do this. There is nothing better on a hot day than to find a nice spot in a shade and dig a cool hole to lay in.
If it doesn't make sense to you, try it. I'm telling you, no air-conditioner will do a better job. The ground is always nice and cool, particularly in the shade, and particularly deeper down.
There are certain spots which are particularly favored for this, and each of them features its own custom-made Grand Canyon.
4. Because it's fun
Some sandy or muddy spots seem to be particularly suited for this purpose. Perhaps it's the way it feels to the paws. All of our guys would get all excited and start digging, just before they go nuts playing and chasing each other.
There is clearly no other purpose to this than fun.
How to stop a dog from digging?
I usually don't try. Why spoil the fun? If they make a hole some place where I don't want one I just bury it later.
The only exception is when Cookie starts digging hard at the roots of a tree (trust me, she'd rip out the roots in the process). In those cases, telling her "let's not hurt the tree" actually seems to work. I know, right? But it does.
For those with fancy flower beds, there are a number of great articles on how to make a designated area for dogs to dig in. I think that's a great idea. Make a doggy "sandbox", have your cake and eat it too. Everybody wins.
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