The best way to keep rats or mice out of a warehouse is to stop them at the perimeter. Eliminating conditions that attract rats and mice to the outside of the building can reduce mouse problems inside the building. Once you have rats or mice nesting or forging around the outside of a warehouse, it's only a matter of time until they find their way inside. Consider that young mice only need a slotted opening about 3/8 of an inch wide, just slightly larger than the thickness of the average pencil. Young rats only need about 1/2 to ¾ of an inch. Below are some things that will attract rats and mice to the outside of a warehouse:
- garbage stored closer than 50 feet from doors
- food or spillage around loading docks, dumpsters, compactors, delivery trucks or rail road tracks
- open lids on dumpsters and garbage cans
- odors from garbage or wild animals
- warm, sun-reflecting walls in the fall and winter
- piles or stacks of trash, building materials, pallets, etc
- equipment stored outside, especially in seedy areas
- dense low growing shrubs around foundations that provide cover and hide burrows and food trash
- tall weeds, grass or vines
- weed growth along fence lines
- fruit trees or crops within 300 ft of a building
- large stones or rock near the building
- railroad tie edging
- ditch, canal, pond or other standing water near the building
- areas of loose soil
- gravel areas with rock of large diameter
- guard dog house or penned yard
- neglected sheds, garage or other outbuildings on the property