Examining the periodicity of annular deposition of otolith microconstituents as a means of age validation

Abstract

— In this study, we examined whether otolith microconstituents are deposited seasonally in a manner similar to optical annulus formation and thereby can be used to validate age interpretations. In temperate species, seasonal temperature changes drive the formation of optical annuli, and we hypothesized that they similarly caused oscillations in microconstituent deposition. Using laser ablation inductively coupled plasma mass spectrometry analysis, we tested for periodicity in the deposition of barium (Ba), calcium, copper, magnesium (Mg), manganese (Mn), phosphorus (P), strontium, and zinc in otoliths and compared that periodicity to the periodicity of the annulus zonation (optical opaque and translucent zones). For this investigation of chemical annulus periodicity, we used black sea bass ( Centropristis striata ), a species with yearly optical annulus formation that has been validated