Day 'N' NightZ

Field study participation and/or data call

Our objective is to sample zooplankton and a few other environmental variables in the full water column of the pelagic zone during the daytime and then zooplankton during the nighttime across waterbodies that exhibit oxic vs. hypoxic hypolimnia. The data will be used to test the hypothesis that zooplankton biomass at night is greater than during the day in the pelagic zone in lakes which exhibit hypolimnetic hypoxia vs. lakes with more oxic hypolimnia. If zooplankton biomass is greater in the water column at nighttime in hypoxic vs. oxic systems, then our estimates of secondary productivity and other zooplankton-related processes in lakes may be underestimated, perhaps severely because historically, zooplankton sampling typically occurs during the day. Although we will not directly sample for DVM vs. DHM in this study, results could emphasize the importance of studying hypoxia and DVM vs. DHM in the future, especially because the extent and duration of hypoxia is predicted to increase in many lakes.