Underwater decomposition: an examination of factors surrounding freshwater decomposition in eastern Massachusetts

Abstract

This study investigated the decomposition of three pig (Sus scrofa) carcasses in the same body of water under lentic and lotic conditions and at variable depths in a temperate mixed forest in the Outdoor Research Facility (ORF) in Holliston, Massachusetts in the summer months of June and July. Data were collected on the invertebrate activity, scavenger activity, water and ambient temperature, stages ofbody decomposition, and the rate of decomposition for each set of remains. Accumulated degree days (ADD) and total body scores (TBS) were used to determine two equations, differentiated by their microhabitat, with the potential use of estimating the postmortem submergence interval (PMSI) in death investigations under similar conditions. The aquatic remains reached skeletonization in 45 days and the terrestrial control remains in 14. Terrestrial and aquatic invertebrate activity was extensive both above and below the waterline with 42 families from 17 orders collected and identified. Through the use of motion detector cameras the researcher was able to view the activities performed around the remains by a blue heron, a coyote, a raccoon, multiple black vultures, multiple turkey vultures, multiple squirrels, and multiple American bullfrogs.