Tracking Hypoxia Exposure in Yellow Perch with Otolith Chemistry: Spatial Variation in Lake Erie

Climate change is producing higher water temperatures and increased precipitation in the northeast. High water temperatures and increased runoff of nutrients can cause the seasonal depletion of dissolved oxygen (DO) in bottom layers of enclosed water bodies, resulting in hypoxia. Despite improvements in water treatment, Lake Erie continues to experience increased hypoxia, driven at least in part by climate change. Stratification causes an extensive hypoxic zone to develop annually in the central basin of Lake Erie, while hypoxia only occurs locally in the shallow western portion of the lake due to wind-driven mixing of the water layers. Hypoxia can have detrimental effects on the growth, development, reproduction and behavior of fish that inhabit the lake. The Lake Erie ecosystem supports a species-rich and diverse fish community that includes the economically important yellow perch (Perca flavescens). Previous studies have indicated that otolith microchemistry analyses using the redox-sensitive element manganese (Mn) can provide individual exposure histories of yellow perch to hypoxia. We compare spatial differences in the duration and frequency of hypoxia exposure in yellow perch between the western and the central part of the lake basin using otolith chemistry.