When we started our research on ridding barns of rodents, we were bombarded with information on preventing them. Yes, of course, we know what we’re
supposed to do to prevent them:
• Use secure metal feed containers.
• Clean up spilled feed right away, using a damp cloth to wipe it up.
• Store alfalfa pellets as securely as sweet feed.
• Fix broken feed room windows or boards promptly, and if you see holes in the siding or walls, seal the areas.
• Screen off vents.
• Remove garbage.
• Cut away shrubbery growing close to the barn walls and doors.
• Feed your barn cats (see sidebar).
Admit There’s A Problem
But what if the rodents have already invaded the premises' First, determine what’s going on. Clues to rodent problems include chewed surfaces, droppings and new holes in walls and corners. Ronald Dues, who owns DSI Pest Control in Stuart Florida, has horse-barn clients. He says rodents prefer to be active at night, so if they feel secure enough to roam in the daylight, there are many.
Consider baiting and trapping by a professional. A pest-control company will identify the rodents and use the correct bait to alleviate the population. They’ll remove the carcasses and dispose of them. Get one that has worked around horses before and check horse-barn references.
Horse owners are understandably concerned about rodent bait, which is, after all, poison. Bait stations are generally tamper-proof and can be placed out of reach of the horses. However, dogs and cats may be at risk, so make changes in their handling or place the bait stations out only in the evenings, when horses are in their stalls and pets are locked up.
Energetic barn owners can handle problems with the help of an agricultural agent who can identify the rodent population and help choose the bait, since, for example, the Norway rat is a meat-eater, while the roof rat prefers grain. Find out how to dispose of the carcasses properly.
Dues recommends zinc phosphide, or tracking powder, made by Bell Labs, sold as ZP Rodent Bait. It goes into a sealed container with an entrance and exit hole. The rodents track through it and take the poison back to the nest, eliminating the colonies.
If you don’t want to use poisons, traps can be used. Place traps near nests. Professional wildlife trappers may also help with your problem (and they’re the ones to call if you’re dealing with small animals like opossums or raccoons). They typically don’t use poisons but trap animals and then seal any access points in feed rooms and haylofts.
Sean Carruth, of Critter Control, a national wildlife trapping company, says you may never be able to completely rid a barn of rats and mice, as the number of entrance points is too vast. Rodents require only a half inch space to access any building. This means a constant watch on making your barn as unattractive to pests as possible.
Monitor potential entrance points for activity by stuffing newspaper in the holes or by lightly taping paper over them to identify if they’re still active. Once the holes are no longer active, seal them with caulk, wood, aluminum, CopperStuff-it or hardware cloth, to prevent the use of that entrance point again.