Landscape fabric would work to cover the hole or even bird netting (unless it chews through it). Do you have any castor oil or ammonia? Perhaps some dumped into the hole might deter it because of the odor.
I once stopped a juvenile raccoon from tipping over a garbage pail by putting ammonia inside the garbage pail and the bag itself. It never came back to it.
☼The best place to seek God is in a garden. You can dig for him there. GBShaw☼