i tend to avoid realy shallow runs , but that doesnt mean you wont catch them there , they tend to use theses when looking for a jump i believe, try to read the hills and look for runs between them usualy between 2 to 7 inch deep on ground where i trap , in time you will just no where a good run is by the slight differance in colour of grass or a very slight depresion in the ground ,if using barrel traps they will most likely need tweeking on the mechanism so they go off easy, also when putting them in the run i wedge the sides with soil from the mound to keep it in place then sprinkle a very light amount (as little as you can get away with )over the trap so as to block out light or outside air as i think it makes them wary , by the sound of things your doing ok though , look for new hills and target them areas , particularly after a downpour , good luck ,arron.