Validation of annulus formation in spotted sucker otoliths

Abstract

Spotted suckers Minytrema melanops are found in many river systems from the Midwest to the Southeast United States. Though they are a relatively abundant species, otolith age validation methods have not been reported. The objective of this study was to validate annulus formation on the lapillar otolith for spotted suckers. We collected spotted suckers monthly from December 2005 to November 2006 in the Apalachicola River, Florida. Using marginal incremental analysis on whole browned lapillar otoliths, we validated that spotted suckers form one annulus per year between May and June. We also report population characteristics including a length–weight regression. This study validates otolith aging to provide an avenue for accurately assessing the age composition of spotted sucker populations, which will facilitate a better understanding of growth, recruitment, and mortality of the species.