Survival and development of copepod larvae Tisbe battagliai in surface microlayer, water and sediment elutriates from the German Bight

During the Bremerhaven Workshop, bioassay techniques using the harpacticoid copepod Tisbe battagliai were employed in shipboard experiments on samples of surface microlayer, water column and sediment elutriates from a contamination gradient in the German Bight of the southern North Sea. The copepod responses measured were survival, growth and development of the nauplius stage to the copepodid stage after 96 h. Significant effects on copepod survival, growth and development were observed in selected samples of surface microlayer, water column and sediment elutriates from different stations. The results for growth and development were more difficult to evaluate than those of survival and the ~nterpretation of these results is discussed in relation to possible interaction with env~ronmental variables. A better understanding of such factors is required before such techniques can be used confidently in the field.