This is perhaps our most common adult fly and although it is a non-biting fly it can be of considerable importance as a pest. Additionally, it has a potential for mechanical transmission of some disease agents due to its presence in decomposing organic and fecal matter. The mouth parts of this fly are modified for lapping up material . This is a non-biting fly that is a serious pest to cattle. It appears to be a recent introduction into North America, first appearing in Oklahoma in 1976.
Adults congregate in large numbers around the face of cattle and other large ungulates.
The adults are most active from spring through fall. There are many species in this genus. Eggs are deposited on objects on or near the surface of the water. After the larval stage pupates, adults emerge in about a week. Although small in size, the adults are good flyers and may go several miles in search of food.