ABSTRACT
Although most studies of the physiological and morphological consequences of stress have emphasized vertebrates, there are indications that counterpart phenomena may be present in invertebrates as well. For Mollusca, several publications have provided evidence for a generalized stress response syndrome. With the clam, Mercenaria mercenaria, for example, a shortened life span, mass mortalities, a reduction in total amino acid and carbohydrate content, and extensive shell invasion by the polychaete worm Polydora were consequences of stress.1 Amino acid ratios, particularly the taurine/glycine ratio in gill and mantle tissues, were considered to be the best indicators of stress. Ratios above 3 indicated stress, with ratios above 5 an indication of acute stress. Exposure of clams to petroleum resulted in black tar-like concretions in amebocytes and in kidney tissues. The concretions collected in the renal sac, plugging the kidney tubules.
