Mice and rats are more of a nuisance than a true threat to adult chickens. While they’re certainly capable of killing chicks, only a very large, very hungry and very motivated rodent will attempt to kill an adult chicken. Rodents tend to view the coop as a warm, dry shelter in which to make a nest, particularly if there is chicken feed to feast on nearby. To get rid of them, the first step is to not attract them.
Eliminate Sources of Food & Water
To begin to eradicate rodents, stop providing a restaurant service in and around your coop. Remove feeders and waterers from your coop and runs at dusk, and clean up any spilled rations that might attract rodents.
Store your feed in tightly lidded metal containers. You can also use heavy-duty, lidded plastic totes, but you will need to inspect these regularly as rodents can chew through plastic.
If you give your flock kitchen scraps, clean anything left uneaten before dark or the rodents will find it. Do not leave pressed seed or suet cakes or other “boredom busters” in any area your chickens frequent, as these will attract rodents as well.
Similarly, don’t leave pet food or wild bird feeders outside overnight. The rodent’s keen sense of smell will quickly locate these.
If you store your household garbage outside, keep it inside your garage instead. Regardless of location, keep your trash secure by storing it in rodent-proof containers. If you have fruit trees, pick ripe fruit frequently and do not leave fallen fruit on the ground.
Collect your hens’ eggs daily to remove that source of food as well. Finally, do not leave sprinklers on at night as these become a source of water for rodents. Check your garden hoses for any leaks that might create standing water from which rats can drink.
Weed Out Potential Nesting Materials & Hiding Places
While rodents may use their own fur to line their nests, they’ll happily utilize anything at hand.
Avoid using straw or lawn clippings in your chicken runs. Not only can rats hide in these, but they’ll carry it down to their nests as lining.
Keep your lawn mowed to eliminate tall grasses where rodents can hide, and be sure to trim or weed whack any plant that grows taller than 12 inches near your coop, your run fence and other buildings.
Dryer lint blown out of vents is another favorite, so make certain to regularly check these openings. If possible, close them off with quarter-inch hardware mesh.
Eliminate piles of junk on your property. Rodents love the hiding places clutter creates. Rats also frequently turn piles of firewood into dens, so keep your logs neatly stacked, at least 18 inches off the ground and well away from walls and fences.
If roof rats are a problem, trim any branches that overhang your coops and run or touch overhead wires or other trees. And prune back any ivy growing on the walls or branches that drape down to the ground.
Evicting Resident Rodents
All of these precautions will make your coop and property less inviting to rodents, but you still have to deal with the ones that are already in residence.
Snap traps are an effective countermeasure to a rat infestation. If you have identified burrow entrances or runways, set snap traps near these holes and heavily traveled areas.
Peanut butter, oatmeal and pet food can be used as bait, but we have had great success using chicken feed. Be certain that you do not set up the traps until your flock is locked up for the night and your pets are inside. A snap trap can seriously injure or even kill a curious animal.
Like other sources of food, remove the traps during the daytime, preferably before a chicken decides to investigate it.
Electronic traps are also highly effective. These usually run on batteries, lure a rat in via ultrasonics, then zap it once it is inside.
Somewhat less effective are glue boards, which are similar to fly paper except for rodents. These work well for mice, but the larger rat can wrest itself out of this sticky situation.
Set Colony Traps
Colony traps are multicatch traps, meaning they can hold more than one mouse at a time. The small metal boxes have an entrance hole on either end that contains a one-way door, meaning mice enter and can’t get out. The nice part about them is they’re on duty 24/7 without maintenance, except for removing trapped mice. Again, no bait is needed if placed against the wall in the normal travel route. All mice caught in a colony trap will be alive if you check them frequently, so you will need a plan for dealing with them. Mice are not at all wary of these devices and will enter them readily.
Colony traps are like small cages. Again, the rats will hesitate to enter them at first. My experience is once one finally goes in, they all go, but it might take days or even weeks.
Poisons are often a last resort for the chicken keeper and should be used with caution around your livestock or poultry. Always place poisons in containment boxes. In most areas, this is the only legal way to use them.
Make sure the boxes are locked in some manner. Many of them snap shut and require a tool to open, while others need to be locked with a screw or similar fastener. This will keep them from opening and exposing the contents to nontarget animals.
I prefer poison blocks over pellets, as the blocks can be fastened to the inside of the box and are more difficult for rodents to remove. Pellets can easily be removed from the boxes, which is hazardous to your flock.
When using any rodenticide, don’t continually use the same one over and over, as rodents will eventually build up an immunity to the chemicals. If a rodent snacks on a poison block and gets a bellyache and then recovers, it’s now immune to that particular cocktail, so change it up frequently. Also, keep the boxes maintained—don’t run out of poison—and keep them well-fed.
Be aware of secondary poisoning to domestic animals, such as cats and dogs, and in wildlife that might consume poisoned rodents. Secondary poisoning is rare, but it can happen.
Disposing of a rodent requires extra precautions, due to the diseases and parasites it carries on its fur and skin. Use disposable gloves to pick up the body, then double bag it in plastic bags and place it in your garbage bin.
Do not leave a rodent in a trap for long, as it will draw insects that can spread any diseases the rat carried. Also, the carcass can end up a source of food for other rats and any scavengers you have in the area.
This article originally appeared in the May/June 2023 issue of Chickens magazine.