Effects of contamination on scavenging beetles

Sunday, November 15, 2015: 2:14 PM
211 B (Convention Center)
Ansley Silva , Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA
Kamal Gandhi , D. B. Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA
David R. Coyle , Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA
James Beasley , University of Georgia, Aikens, SC
Kelsey Turner , Savannah River Ecology Laboratory, Aikens, SC
Erin Abernethy , Savannah River Ecology Laboratory, Aikens, SC
Energy production systems such as nuclear reactors and coal-burning stations produce substantial waste containing radioactive and metal contaminants, respectively. These contaminants can have a significant, yet subtle, effect on biotic communities. To date, most of the existing literature has focused on effects of anthropogenic contamination on invertebrates in aquatic environments, while little is known about invertebrate communities in terrestrial ecosystems. Since biotic community dynamics can influence ecosystem functions, I propose to investigate the influence of metal and radionuclide contaminants on scavenging insect assemblages, species that may act as bioindicators of contamination. My main research objectives are as follows: 1) to assess the effects of two types of contamination (coal fly-ash and radiocesium) on beetle carrion assemblages; 2) to determine if individual carrion insects active closer to contaminated sites may accumulate elevated levels of metals and radioactivity in their bodies. I will use pitfall traps baited with rabbit carrion to collect carrion insects of the Order Coleoptera around water with known types of contamination, including coal-fly ash and radiocesium, in addition to control sites without contamination. For research objective one, 6-10 transects will be established at each site, with four baited pitfall traps along each transect. Transects will be spaced at least 75 meters apart, and 100 meters between traps within transects. Once traps have been installed, I will collect all coleopterans from the traps after seven days. Specimens will be sorted and pinned in the lab and identify to species level using the keys for coleopterans in the southeastern, U.S.
I expect to collect the following beetle families: Histeridae, Scarabidae, Silphidae, Staphilinidae, and Trogidae. Analysis of variance (ANOVA) will be used in R software to assess differences in beetle trap catches between uncontaminated sites and contaminated. Multivariate analysis using either VEGAN 2.0-3 package in R Statistical Computing software, or PC-ORD will be used to assess differences in insect species composition, species diversity,and presence of indicator species between site-types. I will investigate shifts in coleopteran species composition relative to distance away from a permanent source of water, in addition to distance away from a contamination source. For research objective two, I will focus on the most abundant carrion beetle species. Baited pitfall traps will be established as in objective one, however there will be four traps close to the water’s edge and four traps 300 m away at the three uncontaminated and contaminated sites. I will use ICP-MS and Automated Gamma Counting to assess metal and radioactivity levels in about five-ten individuals per trap.  ANOVA will be used to determine the differences in various metals and radioactivity between uncontaminated and contaminated sites