Mice in the chicken coop and feed room: what actually works

Where there’s chicken feed, there are mice. They eat it, they foul what they don’t eat, and they move into the warm bedding. The usual fixes are a poor fit around a flock: poison can reach the birds, and a snap trap on the coop floor can catch a curious hen’s toes. Here’s what works instead.

Start with the feed

Mice stay because of food, and in a coop that means feed.

• Store it in metal. Galvanized cans with tight lids. Mice chew through feed bags and plastic bins.
• Clean up spills around the feeder and the bins. A scattering of pellets is supper for a mouse.
• Take feed away at night, or use a treadle feeder that only opens under a hen’s weight. Mice do most of their eating after dark, while the flock is on the roost.
• Collect eggs daily, and don’t leave kitchen scraps out overnight.

Seal the coop

A mouse can get through a gap about a quarter inch (6 mm) wide.

• Chicken wire keeps chickens in. It doesn’t keep mice out. Cover vents, windows and gaps with quarter-inch hardware cloth instead, fastened from the outside.
• Pack small holes with steel wool or copper mesh, then caulk over them.
• Check where the walls meet the floor, and around doors and pop doors.

Trap without hurting the flock

• No poison. Chickens eat mice when they catch them, and a poisoned mouse can poison whatever eats it, including your birds, your dog, and the owls doing you a favor.
• Keep snap traps out of reach of birds. If you use them, put them inside a box or a length of pipe a hen can’t get into.
• A bucket trap works well in the feed room, the shed where feed is stored, or anywhere else mice travel that the flock can’t reach. It catches mouse after mouse without resetting, and there’s no spring to hurt a bird. See how bucket traps work.
• Keep the bucket away from the birds. A bucket with water in it is a drowning hazard for chicks, small birds and small children. Don’t set one inside the run or the coop where the flock can reach it.
• Go where they run: against a wall, near droppings, gnawed bags or the feed bins. Bait lightly with peanut butter, and give it a few nights, since mice are wary of anything new.

Keep at it

Mice breed quickly, and a feed room is always going to tempt them. Keep a trap set there all year, check it every day, and walk the coop walls each season for new gaps.

Rats are a different job

Rats leave bigger droppings (about half an inch or more), dig burrows, and can take eggs and chicks. A mouse trap won’t handle them. Ours is sized for mice. If you’re seeing rat signs, deal with those separately.

Barn cats

They help, and a lot of farms swear by them. But a cat catches some of the mice, not all of them, and it won’t do anything about the feed that keeps bringing more.