Assessment of Bycatch and Lost Fishing Gear in Sea Bass (Dicentrarchus labrax) Fishing Using Vertical Setline in the Coastal Waters of Yumurtalık Bay

Year 2024, Volume: 7 Issue: 2, 146 - 153, 25.12.2024

Caner Enver Ozyurt

https://doi.org/10.46384/jmsf.1523538

Abstract

In this study, conducted in Yumurtalık Bay (Adana/Turkey) between October 2020 and February 2021, 40 commercial fishing operations were monitored. During the fieldwork, the length and weight of the species caught by commercial fishers were measured, and the number of deployed set lines and the lost set lines were recorded for each operation. The results showed that, aside from European seabass (Dicentrarchus labrax), only six species were caught, with bycatch species constituting 4.64% by weight. Of the 859 seabass individuals caught, only 88 were found to be below the minimum legal catch size (25 cm) specified in Turkish fisheries regulations. These findings suggest that the method demonstrates species and size selectivity, indicating an environmentally friendly fishing approach. A total of 4791 set lines were deployed during the monitored operations, of which 198 lines (4.13%) were lost. The total number of set lines lost by the entire fleet in a single season was estimated to be approximately 2800 lines. While the reasons for gear loss typically include gear conflicts, adverse weather conditions, operational errors, maritime traffic, and vandalism, this study did not specifically identify the causes of gear loss. However, inferences were made regarding possible causes based on previous studies.

Keywords

Dicentrarchus labrax, Small scale fisheries, Northeastern Mediterranean, Bycatch, Fisheries management

Yumurtalık Koyu (Adana/Türkiye) Kıyısal Bölgesinde Levrek (Dicentrarchus labrax) Avında Kullanılan Bırakma Olta Takımının Hedef Dışı Av ve Kayıp Av Aracı Bakımından İncelenmesi

Abstract

Yumurtalık koyunda (Adana/Türkiye), Ekim 2020 ile Şubat 2021 tarihleri arasında gerçekleştirilen bu çalışmada, 40 ticari balıkçılık operasyonu takip edilmiştir. Bu saha çalışmalarında, ticari balıkçılar tarafından yakalanan türlerin boy ve ağırlıkları ölçülmüş, ayrıca her bir operasyonda denize atılan bırakma oltası sayısı ile kaybolan olta sayısı kaydedilmiştir. Elde edilen sonuçlar, levrek dışında sadece 6 tür yakalandığını, hedef dışı türlerin ağırlıkça oranın %4,64 olduğunu göstermiştir. Yakalanan 859 levrek bireyinin sadece 88 tanesinin, ülkemiz balıkçılık mevzuatında belirtilen avlanabilir asgari boydan (25cm) küçük olduğu belirlenmiştir. Bu sonuçlar, yöntemin tür ve boy seçiciliği açısında çevre dostu olduğu fikrini vermektedir. Takip edilen operasyonlarda toplam 4791 adet bırakma olta denize atılırken, bu oltalardan 198 tanesi (%4.13) kaybolmuştur. Tüm filonun bir sezonda kaybettiği bırakma olta sayısı yaklaşık 2800 adet olarak tahmin edilmiştir. Av araçlarının kaybolma nedenleri olarak; av araçları arasında çatışma, kötü hava koşulları, operasyonel hatalar, deniz trafiği ve vandalizm gibi nedenler görülmekte ise de bu çalışmada kayıp nedenleri konusunda herhangi bir tespit yapılmamıştır. Bununla birlikte, daha önce yapılan çalışmalar dikkate alınarak olası kayıp nedenleri hakkında çıkarımda bulunulmuştur.

Keywords

Dicentrarchus labrax, Küçük ölçekli balıkçılık, Kuzeydoğu akdeniz, Hedef dışı av, Balıkçılık yönetimi

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