Moles

Lately a new feature has begun to appear in our back yard:  Little divots, randomly scattered throughout the lawn, as though a golfer or a kid with a shovel has been through here.  Very annoying.

Our neighbors have been afflicted by moles, so I suppose it was a matter of time before some of the creatures decided to move in with us too.  Apparently it's illegal to poison or trap them, so unless we decide to welcome the extra aerating for the lawn, we will have to hire a licensed professional.  Any suggestions?