Meeting Abstract
The Deepwater Horizon (DWH) oil spill led to the exposure of many commercially and ecologically important species to crude oil at early life stages. This oil contains toxic polycyclic aromatic hydrocarbons (PAHs), and exposure has been shown to result in lethal and sub-lethal effects. In particular, sub-lethal exposure is known to result in substantial cardiac impairment, which may have ecological consequences related to reduced oxygen supply capacity and exercise performance. This study therefore sought to explore the impacts of sub-lethal oil exposure on the prey capture ability of early life stage red drum (S. ocellatus) using two test designs. The first test used an open field routine activity assay as an indirect measure of foraging behavior, while the second test directly measured prey capture ability. In both cases fish were exposed to oil via water accommodated fractions for a 24 h period prior to testing. Larvae (21 dpf) exposed to 56 µg/L ΣPAH exhibited a lower total swim distance in the open field activity tests, which is consistent with the hypothesis that cardiac impairment would reduce foraging potential. Similarly, prey capture assays revealed a dose dependent decline in captured food items by exposed larvae (35 dpf), with a significant 3-fold decrease in captured items observed at 56 µg/L ΣPAH. This was coincident with a significant increased time to first and fifth capture. Overall, these data support the hypothesis that the cardiac impairment resulting from oil exposure in early life can result in deleterious performance indices, such as the ability to find and capture prey.
