Success Rates of Recovering Dispersed Bones among Leaf Litter

Abstract

Many outdoor forensic scenes are located in forested areas, and these often require searching through leaf litter to find locally dispersed skeletal remains. Little is known about success rates when processing a scene in this manner, in comparison with previous research on success rates of bone recovery from screening excavated sediments through different size meshes. In order to test recovery rates when searching through leaf litter, ten simulated outdoor scenes sown with disperesed, skeltonized, older juvenile pig (Sus scrofa) bones of different types were processed in succession. All bones had variable brown staining from previous decomposition and burial to include the effects of natural camouflaging typical to forensic scenes in this envrionment. Their sizes were comparable to intact human juvenile reamins or partial adult remains, with some overlap with adult human remains. Procession was executed through a hand-and-knee crawl while picking through all leaf litter by hand and dumping it off-site, leaving behind topsoil with all discovered bones makred by pin flags. Recovery rates ranged from 68.1% to 81.9% per trail, with an overall recovery rate of 76.7% (n=853 elements). Significiant differences in recovery rate based upon bone size category were noted, and a significant downward trend for recovery rates was noted over time, indicating that cumulative searcher fatigue may have played a role. Forensic archaeologists are cautioned that full recovery cannot be assumed in these situations. Careful searching by hand is recommended to mitigate the loss of evidence and should be integrated into all forensic search protocols.