Reliability Assessment of Season-of-Capture Determination from Archaeological Otoliths

Abstract

A technique involving microscopic examination of otolith growth <br /><br />zones has been commonly used by archaeologists along the coast of California <br /><br />to estimate season-of-capture of prehistoric fishes and to infer the season of site <br /><br />use. A test of otolith edge analysis techniques was performed on modern otoliths <br /><br />by estimating season-of-capture for otoliths with known dates of capture. Suc- <br /><br />cessful identification of season-of-capture was low, even in a best case scenario <br /><br />with the age-validated spotted sand bass (Paralabrax maculatofasciatus), empha- <br /><br />sizing the subjectivity of this kind of analysis and inherent variability of growth <br /><br />zone formation in otoliths. Alteration of the otolith matrix from environmental <br /><br />factors further complicates the determination for archaeological otoliths, but surf- <br /><br />perches (family Embiotocidae) hold promise for future studies. This study has <br /><br />called into question the validity of protocols that have not utilized age validated <br /><br />otolith collections and begs caution when estimating season-of-capture from oto- <br /><br />liths.