Why Flies Gather Around Chickens and What to Do About It

Flies swarm chicken coops because they find everything they need there: moisture, warmth, and decaying organic matter in bedding and spilled feed. The problem gets worse in summer and after rain, when conditions become ideal for fly reproduction. You can reduce the fly population significantly by removing what attracts them—wet bedding, uneaten food, and manure—and by using physical barriers or traps that target the flies already present.

The most effective approach combines three steps: eliminate breeding grounds, manage the environment to make it less hospitable, and remove adult flies before they lay eggs. You do not need chemicals or expensive equipment. Most of what works costs little and uses materials you may already have.

Key Takeaways

  • Flies breed in wet bedding and accumulated manure, so removing soiled bedding every two to three days and keeping the coop dry stops most reproduction before it starts.
  • Spilled or uneaten feed attracts flies and gives larvae a food source, so feed only what your chickens will finish in 30 minutes and store grain in sealed containers.
  • Compost manure in a separate bin at least 10 feet from the coop, or let it dry completely in the sun before spreading it on garden beds.
  • Fly traps using apple cider vinegar, sugar water, or commercial sticky traps catch adult flies and reduce the number that lay eggs in the coop.
  • Proper ventilation and drainage prevent the moisture that fly larvae need to develop, so check that water does not pool under feeders or waterers.

Remove Wet Bedding and Manure Before Flies Lay Eggs

Fly larvae develop in moist organic material, and the bedding in your coop is their ideal nursery. Check the coop every morning and remove any bedding that is wet, matted, or visibly soiled with manure. In warm weather, do this every two to three days even if the bedding looks dry on top—moisture underneath is where larvae live. Use a small shovel or garden fork to turn over the top layer and expose any damp spots.

Do not pile removed bedding near the coop. Flies will breed in it there just as readily as they did inside. Either add it to a compost bin that is at least 10 feet away, or spread it thinly in the sun to dry completely. Wet manure takes one to two weeks to dry in hot weather; turn it every few days to speed the process. Once it is completely dry and crumbly, flies cannot breed in it.

Replace soiled bedding with fresh, dry material. Pine shavings, straw, or sand all work well. Sand is particularly useful because it dries quickly and does not hold moisture the way straw does. Avoid cedar shavings—they can irritate chickens' respiratory systems—and do not use hay, which stays damp and compacts easily.

Control Moisture and Drainage in the Coop

Flies need water to breed, and standing water or damp ground gives them exactly what they need. Walk through your coop after rain or watering and look for puddles, especially under feeders and waterers. If water pools in one spot, either move the feeder or waterer or dig a shallow trench to direct water away from that area.

Waterers leak and spill constantly. Use a waterer designed to minimize spillage—nipple waterers or bell waterers with a drip pan underneath work better than open troughs. Check the pan daily and empty it, or drill a small hole in the pan so water drains away rather than pooling. If the ground under the waterer stays wet, add sand or gravel to absorb moisture, or move the waterer to a different spot.

Ventilation matters more than most people realize. A coop with poor air circulation stays damp even when bedding looks dry. Make sure air can flow through the coop—vents on opposite walls work best—and avoid blocking them with tarps or boards except in extreme cold. Better airflow dries bedding faster and makes the environment less attractive to flies.

Manage Feed to Prevent Attracting Flies

Uneaten feed is a magnet for flies and a food source for their larvae. Feed your chickens only what they will finish in about 30 minutes. Scatter feed on the ground or use a feeder, but remove any that remains after half an hour. In hot weather, reduce the amount even more—chickens eat less when it is warm, and leftover feed spoils quickly.

Store grain and other feed in sealed metal or plastic containers with tight-fitting lids. Cloth bags and cardboard boxes let flies and other insects in. Keep containers in a cool, dry place away from the coop if possible. Spilled grain attracts flies when ready, so sweep up any grain that falls during feeding and do not leave bags open.

Treat treats the same way. Scratch grains, mealworms, and kitchen scraps should be given in small amounts that chickens finish quickly. Do not leave vegetable scraps or fruit in the coop overnight. If you compost kitchen scraps, keep that bin far from the coop and cover it so flies cannot reach the contents.

Use Traps to Catch Adult Flies

While you are eliminating breeding grounds, traps will catch the flies already in and around the coop. The simplest trap uses a jar, a piece of fruit or vegetable, and apple cider vinegar. Fill a jar halfway with apple cider vinegar, add a tablespoon of sugar and a drop of dish soap, and set it near the coop. Flies are attracted to the vinegar smell, land on the surface, and the soap breaks the surface tension so they sink and drown. Replace the jar every three to five days or when it fills with dead flies.

Sticky traps work just as well and require no setup. Yellow sticky traps attract flies better than other colors. Hang them near the coop entrance, above feeders, and in any corner where you see flies gathering. Check them every few days and replace when they are covered. Do not hang them where chickens can peck at them.

Commercial fly traps that use bait pellets or attractant packets are also effective. Follow the package directions for placement and replacement. These traps work best when placed outside the coop rather than inside, where chickens might disturb them.

Prevent Flies in Compost and Manure Storage

If you compost manure from the coop, manage that pile carefully or it becomes a fly factory. Build the compost bin at least 10 feet from the coop and preferably downwind. Layer manure with dry material like leaves, straw, or wood chips in a ratio of about one part manure to two parts dry material. This mixture heats up as it decomposes, and the heat kills fly larvae.

Turn the pile every week if possible. Turning exposes larvae to heat and disrupts their development. A pile that reaches 130°F or higher will kill fly larvae in a few days. If you do not have a thermometer, assume that a pile that is hot to the touch is hot enough.

Cover the compost bin with a lid or tarp to keep flies from laying eggs on top. Leave small gaps for air circulation, but close enough that flies cannot easily get inside. If you store manure without composting it, spread it thinly in the sun and let it dry completely before moving it or covering it.

Manage Nearby Areas That Attract Flies

Flies breed in more places than just the coop. Check the area around your coop for other sources: spilled water from outdoor faucets, wet grass clippings, pet food left outside, or garbage cans without tight lids. Any of these will attract flies that then move into the coop.

Keep grass and weeds trimmed short around the coop. Tall vegetation holds moisture and provides shelter for flies. A clear zone of at least three feet around the coop reduces the number of flies that find their way inside. If you have a compost pile or manure storage, keep it even farther away and make sure it is not upwind of where you spend time.

If neighbors keep chickens or livestock nearby, flies may be breeding there and migrating to your coop. You cannot control their management, but you can make your coop less attractive by following the steps above. A well-maintained coop with no wet bedding or spilled feed will have fewer flies even if flies are common in the area.

Frequently Asked Questions

Will cleaning the coop more often really reduce flies that much?

Yes. Fly larvae develop in three to five days in warm weather, so removing wet bedding every two to three days breaks the cycle before most eggs hatch. You will see a noticeable drop in flies within a week if you also remove spilled feed and fix any drainage problems. The improvement is fastest in summer when flies breed quickly.

Can I use pesticides or insecticides in the coop?

Pesticides are not necessary and can be risky around chickens and their eggs. The methods above—removing breeding grounds, using traps, and managing moisture—work without chemicals. If you choose to use any product, read the label carefully to confirm it is safe for use in poultry housing and follow all directions exactly.

Do chickens eat flies and help control them?

Chickens do eat flies and some other insects, but they cannot eat enough to solve a fly problem on their own. Chickens are most active foraging in early morning and late afternoon, while flies breed throughout the day. Rely on removing breeding grounds and using traps rather than expecting chickens to manage the population.

How long does it take to see results after I start cleaning more often?

You should notice fewer flies within three to five days if you remove wet bedding and fix drainage problems. The improvement continues over two to three weeks as the population of breeding flies drops. Traps will catch adult flies when ready, but the real reduction comes from stopping new flies from developing in the coop.

What if the fly problem comes back in late summer?

Flies are worst in late summer when temperatures are still warm and manure has accumulated over months. Increase cleaning frequency to every one to two days, replace bedding more often, and check traps daily. A thorough coop cleaning—removing all old bedding and replacing it with fresh material—can reset the problem if it gets out of hand.