Necrophagous insect species succession on decomposed pig carcasses in North Dakota, USA.

Abstract

Necrophagous insect species are widely used during death investigations primarily for the estimation of the minimum postmortem interval, since these species use decomposing organic matter for feeding, oviposition, and larval development. The development stages and successional colonization patterns provide important information for shorter or longer postmortem time intervals. Diptera species are the predominant taxa recovered from decomposed bodies. The temperature variance/seasonality is the main factor affecting the time presence and activity of these species. Other factors, such as geographical location, antemortem conditions, and cause of death, can influence the presence and succession of necrophagous entomofauna. Consequently, successional studies and information regarding species colonization patterns are needed for each geographical region to be used as reference data during death investigations. This study addressed the need to collect forensic entomological data for the State of North Dakota, within the first necrophagous entomofauna diversity report for the month of July 2022, using pig carcasses as human analogs. During the experimental period, 18 species of Diptera and Coleoptera were identified, with 10 new state records, while Calliphoridae was found to be the predominant family. The resulted data on necrophagous insect species diversity and dynamics from exposed pig carcasses will strengthen the current knowledge on forensic entomology in North Dakota and will serve as reference data to be used during death investigations in the Great Plains region.