DEVELOPMENT OF ACARTIA-CLAUSI (COPEPODA, CALANOIDA) CULTURED AT DIFFERENT CONDITIONS OF TEMPERATURE AND FOOD

The pelagic copepod Acartia clausi Giesbrecht was bred 3 times from na uplius stages I and II to maturity at 5, 10, 15 and 20-degrees-C and 4 different rations of autotrophic and heterotrophic food. The rate of development of copepods increased with increasing temperature and food level. At the highest food level the stage duration was almost consta nt through most stages, but development was not quite isochronal. Part icularly at lower food concentrations stage duration became progressiv ely longer with increasing stage of development. The relation between development time and temperature is described by Belehradek's function s at different food levels. These relations predict a generation time of about 50 days at spring bloom conditions and only slightly less dur ing summer due to food limitation. Comparison with estimates in the fi eld from the literature suggests hat food is often limiting during sum mer conditions.