Effects of molting and environmental factors on trace metal body-burdens and hemocyanin concentrations in the American lobster, Homarus americanus

Hemocyanin concentrations in the hemolymph of marine crustacea are dependen t on the molt cycle and on environmental conditions. Studies in our laborat ories have found that hemocyanin levels in blue crabs are reduced after ecd ysis and under conditions of environmental stress (Engel, Brouwer, & McKenn a, 1993. Hemocyanin concentrations in marine crustaceans as a function of e nvironmental conditions. Marine Ecology Progress Series, 93, 233-244). We h ave extended those studies to include the American lobster, Homarus america nus. Hemolymph and digestive gland tissues from Long Island Sound lobsters were analyzed for hemocyanin, copper, and zinc during different stages of t he molt cycle. Hemocyanin, copper and zinc in the hemolymph were highest in premolt stages (D-1-D-4), and lowest in the postecdysal papershell stages (B-1-B-2). Concomitantly, copper in digestive glands decreased significantl y following ecdysis, but no significant changes in the metals bound to meta llothionein (MT) were observed. Copper-MT was the predominant form througho ut the molt cycle, presumably because lobsters were obtained from copper-co ntaminated areas. To examine the effects of environmental factors, intermol t lobsters were collected front locations of different environmental qualit y along the Atlantic coast, and were analyzed for hemocyanin and trace meta ls. In general, animals from areas with a history or contamination showed t he highest hemocyanin concentrations. Published by Elsevier Science Ltd.