Time for a U-turn for an ecosystem-based management of shrimp fisheries in the Sea of Marmara

Year 2025, Volume: 11 Issue: 4, 291 - 303, 01.12.2025

Uğur Karadurmuş , Hakkı Dereli , Mehmet Aydın

https://doi.org/10.52998/trjmms.1722076

Abstract

This study aims to inform sustainable fisheries management strategies by evaluating the contribution of beam trawl fisheries, mainly targeting deep-water rose shrimp Parapenaeus longirostris, to bycatch in the Sea of Marmara (SoM). Field studies were conducted between May 2022 and April 2023 in collaboration with local fishers operating in shrimp fishing areas in southern SoM. The study encompassed 120 beam trawl surveys covering 8.88 km² across randomly selected stations. Biomass and catch per unit effort were analyzed to quantify catch composition and bycatch levels. Over the study period, 3925 kg of marine organisms representing diverse species were collected, with the target species, deep-water rose shrimp, comprising only 24.6% of the retained catch. The remaining catch consisted of bycatch, including both commercial and non-commercial species, as well as the incidental capture of sensitive taxa. Through field-based assessments, this study highlights the inadequacy of current mitigation efforts to address the destructive nature of the beam trawl fishery in the SoM. Despite gear modification efforts to date to increase selectivity and reduce bycatch, no intervention has been entirely successful in eliminating the ecological footprint. Data-driven insights argue for new management strategies, prioritizing alternative solutions and ecosystem-based fisheries management.

Keywords

Beam trawl , Shrimp fishery , Bycatch , Fisheries , Ecosystem-based fisheries management

Ethical Statement

Formal consent is not required for this study. No shark and ray individuals were landed during the study. All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. Field studies were carried out with the permission decision dated 17.12.2021 and numbered E-12907815-140.99-3782900 of the Ministry of Agriculture and Forestry.

Supporting Institution

This work was supported by the Scientific and Technological Research Council of Türkiye (TUBITAK) ARDEB 1002 [grant number 122Y004].

Project Number

122Y004

Thanks

We want to thank the volunteer commercial fishermen in the study area who participated in the sampling studies with their vessels.

Marmara Denizi'nde karides balıkçılığının ekosistem tabanlı yönetimi için U dönüşü zamanı

Abstract

Bu çalışma, esas olarak derin su pembe karidesini (Parapenaeus longirostris) hedef alan trol balıkçılığının Marmara Denizi'ndeki (SoM) hedef dışı av katkısını değerlendirerek sürdürülebilir balıkçılık yönetim stratejilerini bilgilendirmeyi amaçlamaktadır. Güney SoM'daki karides avcılığı alanlarında faaliyet gösteren yerel balıkçılarla iş birliği içinde Mayıs 2022 ile Nisan 2023 arasında saha çalışmaları güney yürütülmüştür. Çalışma, rastgele seçilen istasyonlarda 8,88 km²'yi kapsayan 120 trol araştırmasını içermektedir. Av kompozisyonu ve yan av miktarını belirlemek için biyokütle ve birim çaba başına av miktarları analiz edilmiştir. Çalışma süresince, çeşitli türleri temsil eden 3.925 kg av elde edilmiş olup, hedef tür olan derin su pembe karidesi, toplam avın yalnızca %24,6'sını oluşturmuştur. Geriye kalan av, ticari ve ticari olmayan türler de dahil olmak üzere yan avların yanı sıra tesadüfen yakalanan hassas taksonlardan oluşmaktadır. Saha tabanlı değerlendirmeler yoluyla bu çalışma, SoM'deki algarna balıkçılığının yıkıcı doğasını ele almak için mevcut azaltma çabalarının yetersizliğini vurgulamaktadır. Seçiciliği artırmak ve yan avı azaltmak için bugüne kadar yapılan ekipman değişikliği çabalarına rağmen, ekolojik ayak izini ortadan kaldırmada hiçbir müdahale tamamen başarılı olmamıştır. Veriye dayalı içgörüler, alternatif çözümlere ve ekosistem tabanlı balıkçılık yönetimine öncelik veren yeni yönetim stratejilerine olan ihtiyacı vurgulamaktadır.

Keywords

Algarna , Karides balıkçılığı , Yan av , Balıkçılık , Ekosistem temelli balıkçılık yönetimi

Project Number

122Y004

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