Bioenergetic analysis of prey consumption byBythotrephes cederstroemiin Lake Michigan

Abstract

A bioenergetic model for Bythotrephes cederstroemi was constructed using measured physiological parameters to predict predation rates. The model predicts that juvenile B. cederstroemi will consume approximately 150% of their body weight per day, while adults consume 118% of their body weight per day. These rates are consistent with those of other invertebrate crustaceans. The predicted rate was twice that of an experimental measurement reported for Lake Huron B. cederstroemi; this discrepancy is attributed to experimental artifacts and to differences between B. cederstroemi populations in Lake Michigan and those in Lakes Huron and Erie. The model was most sensitive to estimation of ingestion and assimilation efficiencies and, secondarily, respiration coefficients. This model estimates the consumption rate of B. cederstroemi in Lake Michigan under optimal food resource conditions, and may be useful in predicting the future impact of B. cederstroemi predation on the zooplankton assemblages of other lakes.