Predation by Predators of the House Fly in Poultry Manure: Effects of Predator Density, Feeding History, Interspecific Interference, and Field Conditions

In laboratory assays over a range of predator densities, the range in number of house fly (musca domestica L.) immatures destroyed per predator per day was as follows: the histerid beetle Carcinops pumilio (Erichson) adults, 21–49; C. pumilio larvae, 13–26; the histerid Dendrophilus xavieri Marseul adults, 5–13; the macrochelid mite Macrocheles muscaedomesticae (Scopoli) females, 10–21; the macrochelid Glyptholapsis confusa (Foa) females, 4–10; the parasitid mite Poecilochirus sp. deutonymphs, 2–5; Poecilochirus sp. females, 2–10; and the muscid fly Ophyra aenescens Weidemann third instars, 7–18. Adult C. pumilio destroyed significantly more house fly immatures per day after 5 d of starvation (⁠|x| = 104) than after 5 d of feeding (⁠|x| = 25); starvation and feeding treatments had no significant effect on predation by M. muscaedomesticae and Poecilochirus sp. When C. pumilio adults, M. muscaedomesticae females, and Poecilochirus sp. deutonymphs were tested in various combinations, significant interspecific interference was observed in five of the nine combinations tested and was most pronounced in mixtures of Poecilochirus sp. with C. pumilia. In an experiment in a poultry house with naturally occurring predator populations in manure, estimated mean daily destruction of fly immatures per predator was as follows: C. pumilia adults, 37; C. pumilio larvae, 17; M. muscaedomesticae females, 8; and Ophyra larvae, 25.