Seasonal variatins in seston and in the growth rate of the iceland scallop, Chlamys islandica (O.F. Müller) from balsfjord, 70°N

The absorption efficiency of Chlamys islandica (O.F. Müller) decreases with increasing “dilution” of particulate organic matter (POM) by particulate inorganic matter (PIM), indicating that the scallop's pallial organs do not select POM in preference to PIM. Since PIM constitutes a large but varyibg fraction of the seston, absorption efficiency would alter in the course of the year and contribute to a variation in growth rate. It is found that seasonal changes in the relative concentrations of POM and PIM in seston can explain the seasonal pattern of growth of C. islandica in the Balsfjord.