A Comparison of Three Structures for Estimating the Age of Yellow Perch

Abstract

Abstract The ability to determine the age of fish precisely is essential to understanding the structure and dynamics of fish populations. The goal of this study was to compare three hard structures (scales, otoliths, and dorsal fin spines) for estimating the ages of yellow perch Perca flavescens in an unexploited population in a sanctuary of Pymatuning Reservoir, Pennsylvania. Scales, dorsal fin spines, and sagittal otoliths were removed from 107 yellow perch, prepared, and examined by two independent readers. Ages assigned by the two independent readers agreed 96% of the time when using otoliths, 83% when using scales, and 80% when using spines. Pairwise comparisons (paired t-tests, α = 0.05) indicated no significant differences among the ages assigned using the three methods. Otoliths were the best structure to use for estimating yellow perch age based on high reader agreement and low coefficient of variation (CV). However, we found that scales and dorsal fin spines can be used to adequately describe th...