THE TRACE-METAL ECOLOGY OF ICHTHYOFAUNA IN THE ROCKALL TROUGH, NORTH-EASTERN ATLANTIC

The concentrations of Cu, Mn, and Ni in tissue samples from 230 fish from the Rockall Trough were determined by atomic absorption spectrophotometry. Concentrations of Cu, Mn and Ni were 0.02-23 mu g g(-1) 0.02-6.5 mu g g(-1) and 0.02-10 mu g g(-1) respectively. Cu appeared to selectively accumulate in liver tissues while Mn accumulated in gill tissues. Ni was evenly distributed throughout all tissues examined. Concentrations of all three metals generally decreased with length. Inter-specific differences between teleosts were found to be related to differences in feeding behaviour. There was no apparent concentration of metals through the food chain from prey to sharks. Low concentrations of Cu, Mn and Ni were detected in the water column (Cu 86-103 ng l(-1), Mn