Flatfish Behavioral Responses to Predatory Threat Under Elevated Carbon Dioxide Levels

The direct and indirect effects of ocean acidification have become a growing concern, particularly in high latitude regions where both CO₂ levels and the rate of increase are expected to be the highest. Studies suggest that elevated CO₂ levels interfere with the GABA-A receptor, causing changes in a variety of behaviors. Most ocean acidification (OA) behavioral research has focused on tropical reef fishes; to date there have been no studies examining behavioral responses to OA in any flatfish species. This study will examine speckled sanddab and English sole anti-predator behavioral responses to perceived predation threat under elevated CO₂ levels. Predator odor, alarm cues from injured conspecifics, and sight of a predator will serve as predator cues. Fish will be acclimated to ambient and elevated CO₂ levels predicted to occur over the next 150 years. Fish will be exposed to predator cues during foraging events to examine the tradeoff between foraging and anti-predator behavior. Changes in the type or duration of these anti-predator responses would indicate OA-induced disruption of sensory-mediated behaviors. Results will give better insight into flatfish life history, the range of OA responses in flatfishes, and the potential impacts of OA on the dynamics of diverse marine communities.