Science Serving Maryland's Coasts

Elizabeth Day, Hampshire College

Class Year: 
2002

Project Title: 

The Effects of Contaminated Sediments on Energy Allocation in the Grass Shrimp Palaemonetes pugio

Abstract: 

Exposure of aquatic animals such Palaemonetes pugio to contaminated sediments of aquatic animals such Palaemonetes pugio can cause these animals to increase their metabolic rates and thus change their energy budgets to better cope with the higher accumulation of toxic contaminants in their bodies. Inability to cope with contaminated conditions can lead to increased mortality. To examine changes in the energy budget of the grass shrimp P. pugio under contaminated conditions, we exposed shrimp to a concentration of 12% Elizabeth River sediment. We looked for effects on survival, standard metabolic rate measured by mean oxygen consumption at rest, growth measured by RNA:DNA ratios, lipid storage, and reproduction. We found no significant difference between contaminated and reference tanks for survival, reproduction, or growth. We also found no significant difference between tanks for oxygen consumption rates with the exception of week six, where shrimp from the contaminated tanks had a lower metabolic rate. We found a significant difference between treatments for adult lipid content, with shrimp from the contaminated tanks having higher lipid content. Thus, we did not see any conclusive negative effects of exposure to contaminated sediments on the energy budget of P. pugio.