Decomposition of cadavers in freshwater environment and its use in forensic practice

Bc. Monika Jirsíková

Master's thesis

Abstract:

Diploma thesis deals with the issue of the determination of post mortem interval (PMSI) in dead bodies found in the aquatic environment. Literature research collects the available information about the bodies found in the water. The experimental part describes a trial whose purpose was to verify the data reported in the literature, also to map the actual process of decomposition as well as certain, which invertebrates were involved in degradation of bodies in the aquatic environment of the Czech Republic and finally, assess the data utilization for forensic entomology. For this purpose two freshwater localities were selected: the first with running water and the second with stagnant water. During the experiment purpose 14 rabbit carcasses were used each weighed about 2,500 g and weighted at the bottom of the water source. At the beginning of the experiment, all carcasses in both variants were simultaneously exposed. Subsequently, two cadavers were extracted at predetermined intervals, one from each variant, and evaluated. Sampling interval was given once a week. On all cadavers, the taphonomic changes and activity of the invertebrates were observed. Every organism found outside or inside the body was secured and subsequently determined. The water sample from the vicinity of the carcass was ensured at each sampling and analyzed. The water temperature at both sites was measured three times a day. In river locality: 110 Gammarus fossarum (Koch in Panzer, 1835), 220 Lymnaea stagnalis (Linnaeus, 1758), 276 Planorbarius corneus (Linnaeus, 1758), 127 Erpobdella octoculata (Linnaeus, 1758), 2 Calopteryx splendens (Harris, 1780), 3 Asellus aquaticus (Linnaeus, 1758) and 18 Tubifex tubifex (Müller, 1774) were secured. In pond locality: 10 Gammarus fossarum, 8 Erpobdella octoculata and 128 Tubifex tubifex were secured. In pond locality 75 tadpoles of Bufo bufo (Laurenti, 1768) and 41 tadpoles of Rana temporaria (Linnaeus, 1758) were secured. There were no serious chemical changes of the water mass in the vicinity of the cadavers.

Keywords

Animals, Aquatic environment, Carcass, Decomposition, Forensic entomology

Language used: English

Date on which the thesis was submitted / produced: 18. 4. 2016

Thesis defence

• Supervisor: prof. RNDr. Miroslav Barták, CSc.

Czech University of Life Sciences Prague

Faculty of Agrobiology, Food and Natural Resources

Master programme / field:
Tropical Agriculture / Wildlife Management in the Tropics and Subtropics