Otolith microchemistry of adult autumn and spring forms of Rutilus frisii kutum

There are different methods available to study the life history and migration patterns of fishes, andthe most accurate of which is the study of the otolith microchemistry. In this study, otoliths of maleand female, autumn and spring forms of Rutilus frisii kutum were dissolved and assayed for Sr, Ba,and Ca.Water and fish samples were collected from the southwestern of Caspian Sea and the riversconnected to this sea in autumn and spring (the time of fish migration to the river). And trace elementsCa, Sr and Ba were measured in otolith and water samples using ICP-AES.Statistical comparison between four groups of fish showed no significant difference in the ratio ofSr: Ca and Ba: Ca between autumn and spring forms. However, the Ba: Ca ratio was higher in autumnfemale fish than in autumn male fish.The results of this study indicated that the Ba: Ca content of two fish species was affected by theamount of Ba in seawater and river water, increased Ba uptake by increasing Sr uptake, interactiveeffects between stage-specific metabolism, temperature and food quantity. The results also showedthat autumn female fish enter the lagoon and river earlier than autumn male fish and left there later.

Otolith microchemistry of adult autumn and spring forms of Rutilus frisii kutum Keywords:

Autumn form , Barium , Calcium , ICP-AES , Otolith , Spring form , Strontium