Construction and validation of a body‐length‐based model for the prediction of cladoceran community filtering rates

Abstract

The in situ filtering rates of individual crustacean zooplankton were determined with radioactively labeled yeast cells. In six cladoceran species ( Bosmina longirostris, Ceriodaphnia lacustris, Chydorus sphaericus, Daphnia galeata, Daphnia pulex, and Eubosmina coregoni ) , 93% of the variation in filtering rate could be explained as a power function of body length, completely disregarding species identity, temperature, and time of day. Community filtering rates for individual depths and for the entire water column were calculated from the regression model using body length and abundance estimates derived from various collection devices. Sampling variability contributed a greater proportion of the error in community grazing rate than did error in estimates of individual filtering rates. The model produced accurate predictions for the original study lake and for a nearby lake and also accurately simulated community grazing observations from the literature. The 95% confidence interval around the mean water column clearing rate was about 10–15% d −1 for clearing rates between 10 and 200% d −1 . It is proposed that the model be utilized to study and evaluate the trophic interactions between the zooplankton, phytoplankton, and bacterioplankton communities.