Can Attractive Sticky Traps Be Used to Protect Horses from the Bites of Stomoxys calcitrans (L.) (Diptera: Muscidae)

Abstract

The stable fly, Stomoxys calcitrans (L.), is a bloodsucking ectoparasite that causes irritation and distress to livestock, wildlife, and humans. Both sexes are vicious blood-feeders that feed on a variety of animals. Optically attractive sticky traps have been used to capture stable flies, and some companies claim that sticky traps can protect animals from the bites of stable flies. To further investigate the protective ability of sticky traps, Home and Garden Mosquito (HGM) traps were selected for evaluations at the University of Florida Horse Teaching Unit (HTU). Broodmares coated with fluorescent dust were either tethered to a post in the center of a paddock or released untethered into a paddock. HGM sticky traps were placed at the four compass points and four selected distances from the paddock center to capture stable flies before (unmarked) or after (marked) they visited the horses. More than 40% of flies captured on traps placed closest to the horses were marked. This indicates that the traps did not prevent the flies from visiting the horses. A percentage of marked and unmarked stable flies showed signs of blood in their guts indicating recent feeding. For unknown reasons, the number of stable flies marked with Signal Green dust exceeded the numbers marked with other colors. Although the HGM traps caught ample numbers of stable flies, the traps did not prevent stable flies from feeding on the horses. More work is needed to determine optimal trap placement and densities required to maximize stable fly management with traps.