Stable Flies

Behavior and Habitat

The stable fly is a blood-sucking fly which is of considerable importance to people, pets, livestock, and the tourist industry in states such as Florida. Stable flies primarily attack animals for a blood meal but in the absence of an animal host, will also bite man. Stable flies breed in soggy hay, grasses, piles of moist fermenting weed, grass cuttings, peanut litter, seaweed deposits along beaches, in soiled straw bedding, and sometimes in hay ring feeding sites. The female, when depositing eggs, will often crawl into loose material. Each female fly may lay 500 to 600 eggs, which are quite small and white in color, in 4 separate batches. Eggs hatch in 2 to 5 days into larvae which feed and mature in roughly two to three weeks. Larvae are maggots and transform to small reddish-brown capsules (pupae) from which the adult flies emerge. The average life cycle is 28 days, with males dying shortly after mating and females dying soon after laying all of the eggs. Certain regions of the United States have considerable problems with large numbers of stable flies attacking man. The coastal parts of New Jersey, shores of Lake Superior and Michigan, and western Florida are areas that historically have had severe stable fly problems. Although these areas have the most severe stable fly problems, the fly is numerous throughout most of Florida.