Voles are semifossorial. I had to look that up as well. According to the Miriam-Webster online dictionary, it means that they are sometimes fossorial, which means that they are adapted to digging.

While moles and voles dig up your yard, they differ in appearance and behavior. Moles are not rodents, but small mammals that spend most of their time underground, digging tunnels, says Zachary ...

Vole damage is often confused for mole damage ... Many different types of rodents may be digging up your yard, including squirrels, chipmunks, and even rats. For example, squirrels will bury ...