Trace elements composition in the otoliths of Aphanopus carbo and Aphanopus intermedius

Abstract

The isotopic composition of 11 trace elements was determined using 30 otoliths of Aphanopus carbo from the Azores, Madeira, Canary Islands and Morocco.Oher 20 otoliths of Aphanopus intermedius from the Canaries and Morocco as well as 20 otoliths of Aphanopus spp. from madeira were equally examined. Trace elements fingerprinting successfully that 68,4& of all fish were correctly classified in their regions of origin, suggesting a degree of stock separation. Populations from Morocco and Madeira appeared to be well separated and it is possible that chemistry of waters surroinding Canaries and Morocco are identical or that fish from many regions spend some time in these waters. The concentration of strontium and barium in the otoliths of A. carbo and A. intermedius are significantly different in fish caught in the same areas, suggesting a difference between species in a physical as well as behaviour way.