SREL Reprint #3423

Bioaccumulation of 137Cs in Florida green watersnakes (Nerodia floridana) inhabiting former nuclear cooling reservoirs on the Savannah River Site

M. Kyle Brown1,2, Michaela Lambert2,3, Amelia L. Russell1,2, Tracey D. Tuberville2, and Melissa A. Pilgrim1,2

1Department of Natural Sciences and Engineering, University of South Carolina Upstate,
Spartanburg, SC 29303
2Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802
3University of Kentucky, Lexington, KY 40506

Abstract: The Savannah River Site (SRS) is a 780-km2 United States Department of Energy (USDOE) property with a history of radiocesium (137Cs) contamination in reservoirs associated with the nuclear reactor cooling process. Radiocesium is a long-lived, gamma-emitting radionuclide that can bioaccumulate in biota. The Florida green watersnake (Nerodia floridana) is a primarily piscivorous species with trophic links to terrestrial and aquatic food webs. Large intraspecific size variation and a preference for permanent still waters, including cooling reservoirs on the SRS, make N. floridana an ideal model for studying bioaccumulation of 137Cs in a top predator. Our study quantified 137Cs concentrations in N. floridana captured from three SRS reservoirs (Par Pond, Pond B, & Pond 2) with unique contamination histories, and determined if snake 137Cs body burdens increased with body size. We used a NaI gamma detector to determine each snake’s 137Cs body burden. Average 137Cs body burden of snakes from Pond B (0.67 Bq/g ±0.05) was significantly higher than the average 137Cs body burden of snakes from Par Pond or Pond 2 (0.09 Bq/g ±0.05 & 0.03 Bq/g ±0.02, respectively; p<0.01). Of the three locations sampled, Par Pond and Pond B showed significant positive relationships between body size and 137Cs body burdens (r2=0.56, p<0.01 & r2=0.29, p<0.01, respectively). Our results indicated that N. floridana can be a useful model organism for examining the fate and persistence of radionuclides in aquatic ecosystems.

Keywords: radiocesium, bioaccumulation, watersnake, radionuclide, body burden

SREL Reprint #3423

Brown, M. K., M. Lambert, A. L. Russell, T. D. Tuberville, and M. A. Pilgrim. 2016. Bioaccumulation of 137Cs in Florida green watersnakes (Nerodia floridana) inhabiting former nuclear cooling reservoirs on the Savannah River Site. Oral presentations at the 13th Annual USC Upstate Research Symposium; printed proceedings, Spartanburg, SC.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).