Decomposition process and arthropod succession on pig carcasses in Quebec (Canada)

Abstract

Necrophagous arthropods are essential ecosystem decomposers and are important indicator species in the discipline of forensic entomology. Studies around the world have evaluated the succession of arthropods on animal carcasses, but no published data are available for the province of Quebec (Canada). The objective of this study was to evaluate the diversity of arthropods associated with pig carcasses in Quebec, and to determine the colonization sequence of the different families/species throughout the decomposition process. Three pig carcasses were deposited in a small woodland area in Trois-Rivières, in mid-June 2019. The decomposition process and the arthropod community were studied until the beginning of November (first snowfall) by visual observation, and sample collection on the carcasses, using an entomological net and pitfall traps. Five species of blow fly (Diptera: Calliphoridae) were found to lay eggs on the carcasses: Calliphora livida, C. vomitoria, Lucilia illustris, Phormia regina, and Protophormia terraenovae. Eggs/larvae of the first three species were recorded during the first week only (fresh stage-beginning of active decay), while the other two species were recorded throughout the decomposition process until the dry remains stage. Coleoptera were observed from day 0 to day 141 (end of experiment). Some families/species were associated with early stages of decomposition (e.g. Necrophila americana, Silphidae), while others were only found during the dry remains stage (e.g. Carnicops pumilio, Histeridae).