Predation by Carcinops pumilio (Coleoptera: Histeridae) and Macrocheles muscaedomesticae (Acarina: Macrochelidae) on the House Fly (Diptera: Muscidae): Functional Response, Effects of Temperature, and Availability of Alternative Prey

Abstract

Rates of house fly, Musca domestica L., destruction by Carcinops pumilio (Erichson) adults and Macrocheles muscaedomesticae (Scopoli) females at two densities in a poultry manure substrate were determined at 27°C as a function of prey availability, and models based on the disk equation of Holling fit the observed data closely (R² > 0.92). Asymptotic predation rates were 54 fly immatures destroyed per predator per day for C. pumilio and 17 and 11 for M. muscaedomesticae at 5 and 20 mites per assay container, respectively. At 15 and 33°C, predation rates of C. pumilio were 12.3 and 82.7 per day, respectively, and those of M. muscaedomesticae were 5.0 and 36.3 per day, respectively. C. pumilio destroyed significantly fewer house flies when acarid mites (Caloglyphus sp.) were present as an alternative prey than when only fly immatures were present; there were no reductions in predation on the house fly in the presence of nematodes (Diplogasteroides sp.) or sphaerocerid (Coproica hirtula Rondani) immatures. M. muscaedomesticae destroyed significantly fewer house flies when nematodes and sphaerocerids were present than when only fly immatures were present; there was no reduction in predation on the house fly in the presence of acarid mites.