A paint roller sometimes can be a helpful tool used to crush (mash) concentrations of newly emerged flies, reducing needless and expensive insecticide applications. It takes newly emerged flies 24 hours before they can fly. Watch every day the stages of fly development. Mature, large fly larvae will slowly change into pupae in three to seven days out of the manure at edges around posts.
Operate manure scrapers every time the feeders are operated to effectively scrape fresh manure droppings down into the pits.
Many types and styles of fly traps appear on the market each year. These traps are usually electrical, employing a black light with an electrically charged grid to kill the insects. Some traps are baited with a fly attractant material.
Traps do appear to be helpful in tight, enclosed areas such as egg rooms, where there is a breeding fly population, if good sanitation practices are followed. However, in areas of heavy fly populations, traps are not effective in reducing fly numbers to satisfactory levels. Use traps in the middle of the night away from doors and windows.
One should judge a trap by the population of flies remaining in the area and not by the number of flies caught in the trap. Most entomologists feel that fly traps, especially where used alone, are not an effective method of controlling flies, especially in and around livestock and poultry operations.
Use good tight screens on the poultry house doors and windows. Use screens 14 to 16 mesh to the inch. Copper, aluminum, bronze, plastic or rust-resisting screens are best.
Use a fan to blow air through a screened doorway from the egg room or other work area into the main poultry house. Flies will not move against the wind into the egg room or other work area. There are commercial electric-powered air curtain fans. However, certain state health departments may require solid doors between the egg room or other main work area into the main poultry house.
Use sticky fly strips where appropriate.
It is important to monitor fly populations in order to make wise control decisions. Visual observations alone can be misleading. One needs to know the fly's behavior patterns and history. Documentation is very helpful in legal defense if needed.
Moving tape count-is the best surveillance method taking about five minutes each day walking on a 1,000 foot walk to catch 25 to 75 flies. Walking down and back in each house is cheap and easy. Use the same walk pattern, the same time of day, when carrying the sticky fly tape.
Sticky fly tapes-which hang, often tell nothing. Tapes fill up fast during the summer months within a chicken house. However, one can determine fly species. Some hang sticky fly ribbons along aisles. Captured flies are counted weekly and ribbons replaced. A weekly count of 100 flies per ribbon may indicate fly control is required. Ribbons may become ineffective after two to three days due to dust and fly covering. They are messy to use and location is important.
Speck fly count-a three inch by five inch white file card fastened flush against feed troughs, ceilings, braces or other fly resting areas, left for a period of several days to a week, will provide documented evidence as to the number of "fly specks" counted on a given date, over a period of time within a given house. Place cards on head rafters (three cards per house) and count fly specks on one side. Change cards once each day or week, depending on populations present. Fifty or more spots, per card per week, may indicate fly control measures are required. Place cards in the same position at each renewal. Fly species cannot be determined from the spots. The spot card method is very economical.
Baited jug trap-is more expensive than other sampling methods, but offers greater sensitivity to fly population changes. A plastic milk jug, with four access holes (two inches diameter) around the upper part of the jug with a wire attached for hanging about three feet above the floor around the pit periphery, may indicate need for control. The jug is baited with a commercial fly bait (about 1 oz.) placed inside the jug bottom. Use fly pheromone muscalure (Muscamone) for effectiveness.
Larval sampling-It is most important to walk the pits to determine "hot spots" where the manure appears flattened, wet and contains heavy populations of fly eggs and maggots. Always take a hoe or trowel to sample the larvae present. Keep pits walkable, clean and water-free. "Hot spots" usually appear where water has laid in the manure. Some may carry a knapsack sprayer to treat only the "hot spots" to halt excessive fly larval breeding. Treating manure widely and excessively will kill beneficial agents. It is best not to treat with chemicals in the manure pits. Pit manure should appear tall, narrow, capped and dry with perhaps beetles present to assist in aerating the manure, making it drier. (Manure will cone with proper fly management.) Beneficial arthropods should be monitored and establishment encouraged to suppress fly populations.