An alternative technique that may provide a longer forecast for hatch date prediction is a model based on developmental rate. By using the date of egg extrusion and the developmental rate at a known temperature the hatch date can be theoretically predicted (Tong et al., 2000). In addition to providing more preparation time, this technique has the added advantage of precluding repeated sampling of the egg clutch through the late stages of development, and its associated handling stress.
The aims of this experiment are to measure the effect of incubation temperature on the egg incubation period of P. ornatus and to generate a practical predictive hatch model for a range of culture temperatures by assessing the thermal characteristics of fertilised eggs of this species.