A Comparison of the Otolith and Scale Methods for Aging White Crappies in Oklahoma

Abstract

Abstract Scales and otoliths (sagittae) were taken from a sample of 137 white crappies (Pomoxis annularis) collected by fyke netting from Ft. Supply Reservoir, Oklahoma, in November 1982. Scales and otoliths from each fish were aged independently by three experienced scale readers, none of whom had prior experience aging otoliths. The average percent error and coefficient of variation of the scale method was approximately seven times greater than for the otolith method, indicating a greater degree of precision for the otolith method. No differences were observed in back-calculated lengths derived from measurements obtained from the right versus left otolith. No significant differences in back-calculated lengths up to age 3 for a given year class sampled in successive years were observed for white crappies aged by the otolith method. These results indicate that age and growth data generated from the otolith method would be sufficiently consistent for biologists to recognize yearly trends in growth variatio...