Effects of Carrion Relocation on the Succession of Newly Arriving Adult Necrophilous Insects

Abstract

Ecological succession of necrophilous insects follows a predictable sequence, related to their differential attraction to changing odor profiles associated with carrion and colonizing insects. However, the dependency of insect arrival on the duration of the carrion's residency at a location has not been investigated. To assess the fidelity of necrophilous insects to carrion of specific decomposition ages, independent of its location, we monitored the decomposition of neonate pigs in one field and then simultaneously relocated carcasses of different decomposition ages to an ecologically similar but remote field. We examined the effects of decomposition age and relocation on the assembly of the necrophilous insect community, using a novel vented-chamber trap, which excluded all sensory cues except odors. Community composition differed over a 4-d decomposition period, showing that insects were differentially attracted to pigs of different decomposition ages. There was overall concordance between respective decomposition ages in the two fields, with similar relative abundances of taxa before and after transfer. Although different decomposition ages continued to attract different insects, differentiation of the necrophilous insect communities relative to the age of decomposition was less pronounced after transfer. The results of this study demonstrate that translocating a decomposing body to a new, but geographically and ecologically similar location continues the predicted insect succession, albeit with greater variance, based on olfactory cues alone. Several rare taxa were sampled only prior to relocation, including the first documentation of the invasive hairy maggot blow fly, Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae), in central North Carolina.