ARS | Publication request: Chrysomya rufifacies (Macquart) (Diptera:Calliphoridae) relationship with native blow fly species on decomposing black bear (Carnivora:Ursidae) carcasses in north central Florida

Submitted to: Neotropical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 24, 2012
Publication Date: N/A

Interpretive Summary: Interactions of blow fly larvae were recorded daily on 5 black bear carcasses. Cochliomyia macellaria or Chrysomya megacephala larvae were collected first, then Chrysomya rufifacies layed eggs in multiple locations on the carcasses uninhabited by the other larvae. After 1 week of decomposition, Ch. rufifacies larvae grew to = 12 mm, filling carcasses and replacing other larvae by food competition or predation. Thus C. macellaria and Ch. megacephala were not collected past their 3rd instar feeding stage. The same blow fly species, including Lucilia caeruleiviridis, Phormia regina, and Lucilia sericata, completed 2 development cycles in the 88.5-kg (195 lb) carcass. This phenomenon could complicate or prevent calculation of an accurate post mortem interval.

Technical Abstract: Larval interactions of blow flies were documented daily temporally and spatially on 5 black bear carcasses from June – November, 2002. Cochliomyia macellaria or Chrysomya megacephala larvae were collected first, then Chrysomya rufifacies oviposited in multiple locations on the carcasses uninhabited by the other blow fly larvae. After one week of decomposition, Ch. rufifacies larvae grew to = 12 mm, filling the carcasses and replacing the other calliphorid larvae through food source competition or predation. As a result, C. macellaria and Ch. megacephala were not collected past their 3rd instar feeding stage. The same blow fly species, Ch. megacephala, C. macellaria, Lucilia caeruleiviridis, Phormia regina, Lucilia sericata and Ch. rufifacies, completed 2 developmental cycles in the 88.5-kg (195 lb) carcass. This phenomenon might serve to complicate or prevent the calculation of an accurate post mortem interval.