Meeting Abstract
Meroplankton are often the only motile phase during the life history of many marine species. Thus, investigating the sublethal effects of crude oil and dispersants on molality is an important consideration. In this study we examine and quantify the swimming behavior of barnacle nauplii (Balanus improvises) when exposed to emulsified crude oil, dispersant (Corexit 9500) and a combination applied at 20:1 oil to dispersant ratio. Four exposure durations were tested; 6, 12, 18 and 24 hours at two realistic oil concentrations; 5 uL L-1 and 10 uL L-1. High resolution videography and motion analysis software was used to quantify swimming kinematics of barnacle nauplii under the different conditions. Results show a significant decline in swimming velocity for nauplii exposed to crude oil after only 12 hours at both concentrations tested. At the concentrations tested, Corexit alone does not have a significant influence on nauplii swimming behavior but when combined with oil, it appears to exacerbate reductions in swimming speed. Exposure to commonly applied water accommodated fraction (WAF) and chemically enhanced water accommodated fraction (CEWAF) methods reveal a more significant impact on swimming behavior and mortality. These findings aid our understanding of sublethal effects of crude oil toxicity to marine zooplankton and our ability to predict how exposure to dispersive larval stages may impact the ability to maintain position in the water column and find suitable habitat.
