Invertebrate community successional changes resulting from delayed colonization on ephemeral resources

The decomposition of organic matter is an essential ecosystem function; it is vital to nutrient cycling, food web dynamics, and can impact biodiversity at multiple scales. Carrion may attract a wide range of species with a variety of life history traits. Invertebrate succession patterns on carrion have been well documented for over 150 years. Manipulation of the remains, (e.g., excluding invertebrates), can affect colonization and subsequent decomposition rates. However, few studies have analyzed invertebrate community composition and succession patterns on carrion following insect exclusion.

The goal of this study was to survey invertebrate community composition and succession patterns throughout vertebrate carrion decomposition. Sus scrofa L., carrion were placed in a Midwest temperate forest. Three carcasses were immediately exposed to invertebrates (ACC), while three carcasses were enclosed in a cage to prevent invertebrate access (EXC) for 5 d. After the delayed colonization period, EXC carcasses were exposed to invertebrates. Trapper® max glue traps were replaced every 12 h and invertebrates identified to the lowest taxonomic level. Overall, EXC carcasses had an increased rate of invertebrate succession when compared to ACC carcasses.

Understanding the interactions within and across trophic levels could lead to elucidating mechanisms governing arthropod succession on carrion. There needs to be continued surveying of invertebrates colonizing carrion in various circumstances. In forensics, identification of species and their time of arrival at a resource is vital in providing more refined estimates of period of insect activity, which can correspond with minimum postmortem intervals.