University Of Tasmania
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Validation of age and growth in a long-lived temperate reef fish using otolith structure, oxytetracycline and bomb radiocarbon methods

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journal contribution
posted on 2023-05-16, 20:40 authored by Graeme Ewing, Jeremy LyleJeremy Lyle, Murphy, RJ, Kalish, JM, Philippe ZieglerPhilippe Ziegler
Generating age estimates for long-lived fish requires particular attention to validation because they are usually difficult to age owing to narrow increment structure. A robust validation of the accuracy and precision of banded morwong, Cheilodactylus spectabilis, sampled from Tasmanian waters, was undertaken. Age at the first enumerated increment was established from analysis of juvenile cohorts, and the timing and periodicity of increment formation was established using a quantitative model from oxytetracycline (OTC) mark-recaptures at liberty for periods of up to 8 years. The accuracy of age estimates was examined independently by comparing radiocarbon values in the otolith region corresponding to the first year of growth against the south-western Pacific calibration curve. C. spectabilis is very long-lived, with males and females living to over 90 years of age. Growth modelling revealed a fast initial growth phase, terminating in an abrupt plateau near the asymptotic length. This species displays substantial sexual dimorphism in growth, with males growing to larger sizes than females. © CSIRO 2007.


Publication title

Marine and Freshwater Research






944 - 955




Institute for Marine and Antarctic Studies


CSIRO Publishing

Place of publication


Repository Status

  • Restricted

Socio-economic Objectives

Fisheries - wild caught not elsewhere classified