habitat and vermin are the keys althou not easy unless u live close by and a few off u to burn safely (i think strips off something like 30ft is about the widest the burnt heather should be, narrower is better), althou like bogtrotter said 250 is a bit on the small side to do much effective management. U are really only shooting ur neighbours overspill. U could possibly put some grit containers down to try and encourage them to hang around. If big numbers next door medicated grit might help keep the worm burdens down althou the medicated stuff has to be replaced so many days afore the shooting season wi normal grit