A comparative assessment of the Black Sea anchovy stock using holistic production and analytical age structure models

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2022-3-01

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Akkuş, Gizem
Gücü, Ali Cemal

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The Black Sea anchovy (Engraulis encrasicolus) is economically and ecologically the most importantcommercial fish species in the Black Sea. Therefore, a management plan targeting the maximum sustainableyield has gained importance in recent years. The present study aims to provide a comprehensive assessment byusing only Turkish data to evaluate the status of the Black Sea anchovy stock and compare the differentapproaches outcomes. For this, ASPIC (1968-2014) as a holistic production model and XSA (2005-2014) asan age-structured model are used. ASPIC estimates that the Black Sea's carrying capacity (K) is 1.2 milliontons of anchovy, and to achieve the MSY of 244kton fish, 610kton (BMSY) fish must be present in the sea. Itis estimated B2015 is 399ktons; this shows, now, there are 35% fewer fish present in the sea. Hence, the BlackSea anchovy is exposed to low overfishing. In XSA, the stock-recruitment relationship could not be established.Therefore, the current status of anchovy stock is estimated by Patterson’s (1992) precautionary exploitationrate of Etarget=0.4 as a reference point. Accordingly, the current exploitation rate is calculated as Ecurrent=0.5,which is 25% higher than the Etarget. Hence, XSA results also suggest that the Black Sea anchovy is exposedto low overfishing. This result and the comparable parameter of F of the two models show the concordanceand comparability of holistic (ASPIC) and analytic (XSA) models.

Subject Keywords

Black Sea anchovy, Stock assessment, Analytical age structure model, XSA, Holistic production model, ASPIC

URI

https://hdl.handle.net/11511/101012

Journal

Acta Biologica Turcica

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Graduate School of Marine Sciences, Article

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Citation Formats

G. Akkuş and A. C. Gücü, “A comparative assessment of the Black Sea anchovy stock using holistic production and analytical age structure models,” Acta Biologica Turcica, no. 35(3), pp. 1–12, 2022, Accessed: 00, 2022. [Online]. Available: https://hdl.handle.net/11511/101012.