To capture a mole, place a multiple catch trap such as a Ketch-All in its burrow. Simply dig a hole and insert the trap, so that its opening is aligned with the tunnel. Once the mole enters the trap, it cannot escape.
To determine whether a tunnel is inhabited, inspect the ground closely. Look for a tunnel directly connecting two or more molehills and running along permanent structures such as fences, paved roads, or a line of trees bordering a field.
Another way to detect inhabited tunnels is to step carefully on various small sections of the tunnels, making sure not to collapse them. Mark the areas clearly. After a few days, those sections that are back to their original shapes can be considered as inhabited and a good place for trapping.