EFFECT OF BODY-SIZE AND SEASON ON THE CONCENTRATIONS OF CU, CD, PB AND ZN IN DIASTYLIS-RATHKEI (KROYER) (CRUSTACEA, CUMACEA) FROM KIEL BAY,WESTERN BALTIC

The concentrations of four metals (Cu, Cd, Ph and Zn) in the cumacean Diastylis rathkei were estimated from four stations in Kiel Bay, Weste rn Baltic. Metal concentrations in samples from the four stations were not significantly different from each other. Smaller animals were fou nd to contain less Cu and Cd and more Pb and Zn than larger ones. Seas onality in the concentrations of the four metals was observed. General ly, high concentrations of the four metals occurred during the summer months, which corresponds to the main growth period of D. rathkei. The ratio between monthly maximum and minimum mean concentrations was gre atest for Ph (factor 2.5) and least for Zn (factor 1.4). Cd and Cu had a common ratio of 1.6.