Filth Fly Control on Horse Farms

establishing a control program. This information can help you understand
The options available for that particular pest
How you can interrupt the pests life cycle with the respective control options
Can you identify these flies? Probably not! While identifying some species is easier than others it may be necessary to employ a few monitoring methods to see what flies you actually have before you can learn more about their biology and decide on control methods. Photo by JacLou DL
Four common filth fly pests are discussed in this guide house flies stable flies face flies and horn flies. These fly pests are similar in size shape and color and develop in similar habitats containing fresh or decomposing organic matter.
All the pest flies discussed here have four distinct life stages egg larva pupa and adult. Usually once you start noticing high numbers of adult pests it is too late to do much to quickly solve the problem. However targeted control options are available for each of these fly pests and life stages with the goal being to break or interrupt the life cycle at one or more points and reduce pest numbers.
Not every filth fly is a pest!
While some pest flies can be very common on horse farms other flies that are not necessarily pests can be found and are often confused with fly pests. These flies often develop in trash carrion or other decaying matter but typically do not cause animal or human disturbance. In fact some of these flies like the black soldier fly are actually beneficial in reducing pest fly numbers. If high levels of these flies are present and causing nuisance problems it is best to locate where these flies are developing and remove the source.
Not every pest is a filth fly!
Several species of fly pests are common on equine facilities

that are not discussed in this guide. Black flies deer and horse flies biting midges and mosquitoes are all common biting flies. While these flies are common they do not develop in the same materials as filth flies and an IPM plan for filth flies will not affect these populations. If present a management plan for these specific pests should be developed because they can also transmit pathogens that cause disease in humans and horses.
Learn About the House Fly
General Biology
An adult house fly can lay several clutches of up to 200 eggs at a time. These eggs are laid in organic material with some heat and moisturesuch as in manure soiled bedding spilled feed decaying grass clippings or hay or similar materials. House flies can fly several miles to find suitable areas for development. It is important to identify whether flies are developing on the farm or adults are flying in from neighboring facilities. Total development time from egg to adult depends on environmental conditions the most important of which is temperature. Under ideal summer conditions fly development can occur in as few as seven days.
Identification
Adult house flies are nonbiting flies with sponging mouthparts. These flies are frequently found on the head near the lips nostrils and eyes or near open wounds. Unlike face flies house flies can be seen on all parts of the animal body. House flies have mostly gray bodies with yellowish abdomens four black stripes on the thorax the area of the fly directly behind the head and are about ⅜ inch in length. In general males and females look similar. However it is important to note that size and color may vary among individuals depending on development and local population factors. Posture is another way to recognize different species. At rest house flies hold their