Producers prepare to manage face flies in cattle as warmer weather approaches
While face fly numbers among cattle in the Ozarks are not usually extreme each year, they can still be difficult to manage.
Kelly Loftin, a University of Arkansas Extension entomologist and professor, said there are multiple considerations for those who want to control face flies, including biology, feeding patterns, and treatment options for face flies.
The first peak of these pests can be seen in late June. In Arkansas, the dry summer can cause a second peak in early fall due to rain lowering temperatures and humidity.
Face flies begin their life cycle as eggs in fresh cow manure. The eggs hatch and develop into larvae. After growing, the larvae then pupate in the soil near the manure. The pupae then emerge into adults, with an average life span of 14-21 days.
“The eggs are laid on fresh cattle manure and are species-specific to cattle,” said Loftin.
Once developed into adults, face flies begin feeding. However, unlike the horn fly, face flies do not feed on blood. They do not have biting parts in their mouths that allow them to be blood feeders. These flies have spongey components, which allow them to absorb fluids that provide them with nourishment.
“What they do with these spongey mouth parts is feed on secretions around the eyes, around the nose and on other areas,” said Loftin.
The secretions provide nutrients and protein for the flies.
Face flies are intermittent feeders. When the flies are full, the pests do not remain on the host. They leave to rest and process their consumption in vegetation, buildings, or on any other surfaces they can land on — like fences.
With face flies spending only a small amount of time on the host, controlling the population and treating cattle becomes difficult.
Face fly control treatments should begin when there are around 10 flies per head of cattle. Options include insecticide ear tags, back rubbers with face flips (charged with insecticides) or insect growth regulators like methoprene to treat larvae in the ground.
“The face flips that you tie on to the back rubbers will drape across their face as they pass under it, and that’s very effective on face flies,” said Loftin. “That’s what I would recommend.”
Face flies travel and do not remain in one area. The flies can travel up to four miles, infecting multiple herds. It is imperative for producers to watch their cattle to prevent the spread of face flies.
