Tuesday, December 12, 2006 - 10:17 AM

Attraction of blow flies (Diptera: Calliphoridae) to fresh and aged carrion in northeastern Ohio

Joe B. Keiper, jkeiper@cmnh.org, Jessica Taylor, and Kurt Broz. Cleveland Museum of Natural History, Department of Invertebrate Zoology, 1 Wade Oval Drive, Cleveland, OH

During an investigation into a homicide in northeastern Ohio, USA, a question surfaced regarding whether certain species of blow flies would be attracted to, and oviposit on, concealed bodies that initially decomposed in the absence of insect activity. To test this, we put one lab rat carcass in each of nine chicken wire cages positioned in an old field near Cleveland. Three cages had fresh rats that were laid directly on the vegetation; three cages had fresh rats that were placed within ripped trash bags; the final three cages had rats that were immediately placed in sealed black plastic trash bags and allowed to age at ambient temperatures for one week prior to exposure to insects by ripping the bags open. All treatments were exposed to fly activity in the field simultaneously, and the experiment was run twice (early June and early July). Carcasses were examined approximately daily. Immatures were collected, and half were preserved while the other half were reared to the adult stage. Larvae were identified to subfamily, whereas adults were identified to species. Lucilia illustris, Phaenicia sericata, and Phormia regina were the three most common species. Statistically equal numbers of all blow fly taxa were found on all three carcasses, both during the June and July trials. These data indicate that these three common species, all encountered frequently during homicide investigations, will take advantage of mammalian carcasses as an oviposition substrate regardless of duration of decomposition in the absence of insects.

Species 1: Diptera Calliphoridae Lucilia illustris (green bottle fly)
Species 2: Diptera Calliphoridae Phaenicia sericata
Species 3: Diptera Calliphoridae Phormia regina (black blow fly)

[ Recorded presentation ] Recorded presentation