I have also had to resort to poison this winter. My pantry in the kitchen and all the cupboards and draws were full of mice droppings, i tried live traps and a sonic system but there were so many, it was a health risk in the end. At the chicken coop the rats were having a field day, they were everywhere and at the back if the chicken coop I have a large shed housing the mowers and gardening stuff and they were burrowing and eating through everything in sight. I tried ordinary rat poison sachets but I think they became immune to them, I tried two types of traps but they stayed well away from them, in the end I had to buy extra strong stuff, I put a few down the holes around the coop and left the box of 12 in my shed in the box in a hanging basket. The next day all the sachets had gone, also the rats thank god. That was a week ago and I havnt seen any droppings since, keeping my fingers crossed. It was either the poison or being over run with vermin which was a health risk. If I can save animals the humane way that would always be my first choice but this time it was too much.