Age determination of corvina reina (Cynoscion albus) in the Gulf of Nicoya, Costa Rica, based on examination and analysis of hyaline zones, morphology and microstructure of otoliths |
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| Authors: | M Mug-Villanueva V F Gallucci †‡ Han-Lin Lai§ |
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| Institution: | University of Costa Rica Sede, Limon, Costa Rica;Management Assistance for Artisanal Fisheries (MAAF), School of Fisheries, CQS, University of Washington, Seattle, WA, 98195;Washington State Department of Fisheries, 1111 Washington Street, S.E., Olympia, WA 98504-3144, U.S.A. |
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| Abstract: | This is the first age determination study for Cynoscion albus , a large tropical sciaenid, using otolith morphology and daily increment analysis. The practicality of both methods for age determination is illustrated by their consistent estimates of age and von Bertalanffy growth parameters. The daily increment analysis was used to validate the surface readings. An alternative, otolith morphometrics, is shown to hold promise for rapid prediction of fish age. Two multivariate linear regression models using gross otolith dimensions can estimate the age of C. albus to within 1 year. Growth parameter estimates are: from surface readings: L =127.5cm with K =0.12; from daily increment readings: L = 122.1 cm with K =0.17. Implications for the stock assessment of tropical fish using size instead of age are discussed. |
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| Keywords: | age determination daily increment otolith morphology microincrement analysis tropical Sciaenidae |
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