Seasonal changes of the copper level in shore crabs Carcinus mediterraneus

Seasonal changes in copper content of the shore crab Caicinus mediterraneus Csrn. (whole crab, haemolymph, hepatopancreas and exoskeleton) were studied to establish patterns and to examine fluctuations in the population. A significant decrease in copper content in the haemolymph and hepatopancreas and an increase in the copper space (taken as an estimation of the haemolymph volume) occurred in winter. These changes are closely related to the drops in the protein and copper haemolymph concentrations of the winter crab populations when their activities and food intake are significantly decreased. The copper space strongly correlates with the haemolymph copper content and with the haemolymph copper concentration. On the basis of the haemolymph copper determinations a model of the copper space is described.