Preliminary study on otolith chemistry and otolith morphology of two demersal fish species, European hake Merluccius merluccius (Linnaeus, 1758) and striped red mullet (Mullus surmuletus, Linnaeus, 1758) in the Sea of Marmara

Otoliths are calcium carbonate (CaCO3) accumulations. Under the influence of different ecosystems morphological and chemical composition change. In this study, economically important two demersal fish species; European hake Merluccius merluccius (Linnaeus, 1758) Stripet red mullet (Mullus surmuletus Linnaeus, was examined. (Sagitta) belonging to these species have been studied both chemically morphologicall. Morphometric measurements otoliths (length, mm; width, area, mm2; perimeter, mm) in sagittal each made by Leica M125 tri-ocular microscope. analysis otoliths, strontium (Sr), magnesium (Mg) (Ca) trace element amounts, ratios Sr Mg elements Ca (Sr/Ca Mg/Ca) were determined. For micro-chemical ICP-MS used. The highest (24.92±9.57 mmol/mol) (26.17±1.81 values found otolith mullet. difference between (Sr) amounts for be significant (P<0.05). addition it that them amount is (P<0.001). shape indexes significantly species. Especially terms roundness (RD) aspect ratio (AR) results study provide information about habitats economic importance Since such studies can give habitat areas species, they tracking stocks, migration routes sustainable fisheries.