Hi Banditbob
I can’t say whether there might be a hog in the shed (although, do you mean the gap was into the shed or underneath it). In my experience hogs do not dig to that extent and it sounds more likely that it’s a rat (or other burrowing animal). (rats can create fairly large mounds of soil when excavating a burrow or, even bolt holes). If the soil is blocking a hole into the shed, which hogs may need for access, I would be inclined to clear the accessway, in case. If a hog was nesting near a hole into the shed, it would be more likely to be blocked with vegetation, i.e. grasses, leaves, etc.
