Comparison of Five Calcified Structures for Estimating the Age of Bream Abramis brama (L.) from the Irtysh River in China

Özet

We compared five calcified structures (scale, otolith, vertebra, cleithrum, and opercular bone) for estimating the age ofbream Abramis brama (L.) from the Irtysh River in China. Otoliths consistently had the clearest marks, highest confidencescores, highest between-reader agreement (91.63%), and lowest CVs. Cleithra provided the second-highest between-readeragreement (88.65%) and highest agreement (66.08%) with otoliths. Scales and vertebrae yielded equivalent age estimates thatwere lower than those from otoliths and cleithra, but the estimates of A. brama older than 11 years were consistentlyunderestimated using scales and vertebrae. Opercular bone was inferior to other structures for aging A. brama. Opercularbones resulted in the lowest between-reader agreement (84.68%), lowest agreement with otoliths (62.33%), and highest CVs.According to these findings, we recommend the use of ground otoliths for estimating the age of A. brama when an accurateage structure assessment is required, and recommend scales if a nonlethal procedure is needed for age estimation in order toanalyze simple population metrics of A. brama.