did a contract job , ferreting last week , first day got 25 missed one rabbit. went round with the rifle later that eavning , watched 3 rabbits go in the warren , you are always going to miss a few, and rabbits know if there is a preddator in there warrens.
if you do a good job however, the next time you go you are going to get less and of course you will ferret empty warrens, unless using a marking dog