RESPIRATORY ENERGY EXPENDITURE BY THE PREDACEOUS ZOOPLANKTER LEPTODORA KINDTII (FOCKE) (CRUSTACEA: CLADOCERA)1

Abstract

Respiratory expenditure energy budgets were determined for a natural population of the predaceous zooplankter Leptodora kindtii during two growing seasons. Oxygen consumption, carbon dioxide production, and RQ were determined under a variety of laboratory conditions. Leptodora demonstrated a respiratory regulatory plateau over the temperature range 15 to 25C. Oxygen consumption was highest for males and lowest for fecund females. Annual population maintenance cost (respiration) was calculated to be 22.5 kcal m−3 yr−1 in 1966 and 111.4 kcal m−3 yr−1 in 1967 (4,625 ml O2 m−3 yr−1 and 23,302 ml O2 m−3 yr−1).