Understanding the status of key fish stocks in the Turkish Black Sea: A graphical approach to sustainable management

Mahir Demir

doi:10.12714/egejfas.42.2.03

EN TR

Understanding the status of key fish stocks in the Turkish Black Sea: A graphical approach to sustainable management

Abstract

Fish stocks are critical components of aquatic ecosystems, providing essential food sources for humanity and supporting the complex balance of marine food webs. Effective management of these resources is crucial for meeting global food demands and preserving aquatic biodiversity. In this study, we assess fishing pressures—categorized as low, high, and extreme—on six key fish stocks in the Turkish waters of the Black Sea: horse mackerel (Trachurus mediterraneus), the Black Sea anchovy (Engraulis encrasicolus), sprat (Sprattus sprattus), whiting (Merlangius merlangus euxinus), bluefish (Pomatomus saltatrix), and the Atlantic bonito (Sarda sarda) and provide important findings to protect fish stocks. By applying dynamic modeling and stability analysis solely to landing data, we create graphical representations that illustrate the current trends of these stocks, through growth and fishing mortality curves. Our findings reveal that although certain stocks have shown an upward trend over the past 15 years, they remain exposed to high levels of fishing mortality. To support sustainable management, this study establishes the Maximum Sustainable Yields (MSYs) for each stock based on their present conditions and identifies stable equilibrium points where stocks can be sustained over the long term. This method also provides an opportunity to analyze state of fish stocks when only landing data is available.

Keywords

Karadeniz'deki önemli balık stoklarının durumunun anlaşılması: Sürdürülebilir yönetim için grafiksel bir yaklaşım

Öz

Balık stokları, su ekosistemlerinin temel bileşenleridir; insanlık için çok önemli bir gıda kaynağı sağlarken, besin zincirinin karmaşık dengesine de katkıda bulunurlar. Bu balık stokların etkin bir şekilde yönetimi, gıda taleplerini karşılamak ve denizlerdeki biyolojik çeşitliliği korumak açısından kritik öneme sahiptir. Bu çalışmada, Türkiye'nin Karadeniz kıyısındaki altı ana balık stoğu – istavrit (Trachurus mediterraneus), hamsi (Engraulis encrasicolus), çaça (Sprattus sprattus), mezgit (Merlangius merlangus euxinus), lüfer (Pomatomus saltatrix) ve palamut (Sarda sarda) – düşük/yüksek/aşırı avlanma seviyelerine göre incelenmiştir ve bu stokların korunmasına dair önemli bulgular sunulmuştur. Sadece av istatistikleri kullanılarak dinamiksel bir inceleme ve denge analiziyle, balık stoklarının mevcut dinamiklerini grafiksel temsiller kullanarak analiz ettik. Bu grafikler, balık stoklarının büyüme eğrileri ve balıkçılık kaynaklı avlama (ölüm) eğrilerine dayanarak oluşturulmuştur. Araştırmamız, bazı stoklarda son 15 yılda artış eğilimi gözlense de hala yüksek düzeyde avlanma oranına maruz kaldıklarını ortaya koymaktadır. Bu sorunu ele almak için çalışmamız, her bir balık stoğunun mevcut durumuna bağlı olarak Maksimum Sürdürülebilir Verim (MSV) değerlerini belirlemekte ve bu stokların uzun vadede sürdürülebilir kalabileceği denge noktalarını tespit etmektedir. Bu yöntem, avlanma verileri dışında herhangi bir veri bulunmadığında balık stoklarını analiz etme fırsatı da sunmaktadır.

Anahtar Kelimeler

Ethical Statement

No ethical approval is required for this study.

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Details

Primary Language

English

Subjects

Fisheries Management

Journal Section

Research Article

Authors

Mahir Demir ^*
0000-0002-9670-5210
Türkiye

Early Pub Date

June 14, 2025

Publication Date

June 15, 2025

Submission Date

December 17, 2024

Acceptance Date

March 12, 2025

Published in Issue

Year 2025 Volume: 42 Number: 2

DOI

https://doi.org/10.12714/egejfas.42.2.03

IZ

https://izlik.org/JA42SW62BD

Cite

RIS / Bibtex

APA

Demir, M. (2025). Understanding the status of key fish stocks in the Turkish Black Sea: A graphical approach to sustainable management. Ege Journal of Fisheries and Aquatic Sciences, 42(2), 105-121. https://doi.org/10.12714/egejfas.42.2.03