Ive heard that if you sprinkle the perimeter of your garden with crushed egg shells they hate it because it sticks to thier bellies might be worth a go or old tbags too same reason it sticks to them. Thats the humane way the other is to sprinkle salt on your garden pathways or areas where they go and they will melt like gremlins! yuk! then simply wash off next day. good luck.