Trace elements in cephalopod calcified tissue. Cuttlebone as a possible tracer for life historical events of cuttlefish

Trace elements in a cuttlebone, a buoyant calcified tissue developing simultaneously with the individual growth, of an adult giant cuttlefish originating from the water of Ishigaki Island were measured by PIXE to examine the ontogenetic change of the element concentration. Beside calcium (major element), iron, zinc, manganese, copper, bromine and relatively large amounts of strontium were detected in the cuttlebone. Strontium concentration varied with position along the cuttlebone: it was high near the spine (the portion that deposited at the paralarval stage), then showed some variations at the middle portion of the cuttlebone (the portion that deposited from young stage to sub-adult stage) and became the highest near the locus (the portion that deposited near the catch date, i.e., adult stage). This variation was compared to migration of this species between inshore and offshore waters. (author)