When a mole digs in your yard the mole will make a raised volcano shaped swelling of the dirt in your yard.
They'll basically be small piles of dirt throughout your yard when you have moles.
Walmart sells a Mole and Gopher Repeller that you place in the ground it helps to get rid of and keep moles and Gophers out of your yard.
Moth balls placed in a Gophers hole can also get rid of Gophers in your yard.