When we still lived in Minnesota we had a border collie who spent part of her time in the house. She knew she was not supposed to have anything to do with food in the house. One day Barb noticed that one of the planters didn't look exactly right. (I never would have noticed, but she is quite particular about her plants). As Barb got down for a closer look, the plant seemed loose to her. When she went to pat down the dirt she felt a little lump that didn't seem quite right. Keep in mind that she was now within inches of the plant, with no obvious clues that anything was strange. Going through the dirt to find the "lump", she found a small bag of M&M candies that the dog had buried, presumably for later consumption.
Now that we live in New Mexico, she can behave like a "proper dog", and buries things like elk bones that she finds while patrolling the canyon. But I guess it is all the same type of behavior.
