If like in my setting, the rodent abundance cycles such that all the predators combined cannot keep it suppressed at all times. What can complicate issues is the surroundings not directly in poultry use. Outside barn you can have food and cover allowing build up of rodents despite what barn provides. Over winter I a good number of white-footed mice with some house mice. As the seasons progressed the house mice replaced the white-footed. The house mice do seem more tied to feed spillage. A single young adult tom cat and at least a couple Coopers Hawks worked barn for the mice when weather was cool but now that growing season is well underway they have too many other targets for consumption to waste time in my barn.
