The Limnology of a New Zealand Reservoir, with Particular Reference to the Life Histories of the Copepods Boeckella propinqua SARS and Mesocylops leuckarti CLAUS

The Auxiliary Nihotupu Reservoir, near Auckland, New Zealand, was studied during 1967‐68. The reservoir was emptied for a short time during the study. Changes in physico‐chemical factors, phytoplankton and zooplankton were followed throughout the year. Thermal stratification was evident over the summer and the partitioning of oxygen and pH at this time is discussed. An acid heterograde pH curve is reported. From an analysis of oxygen deficits it is suggested that the reservoir may be oligotrophic. An analysis of egg production, length distributions and changes in developmental stages was used in interpreting the life cycle of Boeckella propinqua. Development times from egg to adult, and approximate survival rates are briefly considered. Mesocyclops leuckarti is also discussed and the annual cycles of both copepods are compared with those in other New Zealand lakes.