Effects of temperature and food on the fecundity and egg development rates of Boeckella symmetrica Sars (Copepoda : Calanoida)

Abstract

The effects of temperature and food regime on the fecundity and egg development of B. symmetrica are presented.

Clutch size decreases with increasing temperature and decreased food availability. At low food levels; there is increased variability in clutch size; this increase is less marked at lower temperatures.

Duration of egg development decreases hyperbolically with increasing temperature; there may be a slight increase with increased food availability. Egg size decreases linearly with increasing temperature: food supply may have some effect. Variability of egg size decreases with decreasing temperature. Egg mortality is highest towards the lower limit of the natural thermal range of B. symmetrica and lowest near the middle.