Güllük Körfezi’nde (Ege Denizi) balık çiftlikleri etrafında yapılan kupes (Boops boops) uzatma ağı avcılığından elde edilen hedef-dışı av oranları

Yıl 2023, Cilt: 40 Sayı: 2, 140 - 144, 15.06.2023

Okan Ertosluk Okan Akyol Tevfik Ceyhan Aytaç Özgül

https://doi.org/10.12714/egejfas.40.2.08

Öz

Bu çalışma, Güllük Körfezi'ndeki (Ege Denizi) balık çiftlikleri çevresinde küçük ölçekli balıkçı tekneleri tarafından uzatma ağlarıyla hedeflenen Boops boops avcılığı sırasındaki hedef dışı avı ortaya koymak ve birim çaba başına hedef dışı av (BPUE) oranlarını belirlemeyi amaçlamaktadır. Çalışma, Kasım-Nisan arasındaki iki sezon boyunca (2017-2018 / 2018-2019), Göltürkbükü, Gündoğan, Yalıkavak ve Torba limanlarında rıhtım örneklemeleri yoluyla gerçekleştirilmiştir. Toplam 13 kupes avcısı tekneden 147 balıkçılık operasyonu rastgele izlenmiştir. Kupes uzatma ağı ile avcılıkta omurgasızlar dâhil 30 familyaya ait 48 türden toplam 18163 kg av yakalanmıştır. Hedef balık olan Boops boops en bol (%91,9) bulunan tür olup, bunun %8,1’si hedef dışı av olarak kaydedilmiştir. Hedef dışı avda en çok yakalanan türler sırasıyla Diplodus annularis (Linnaeus, 1758), Scomber colias (Gmelin, 1789), Trachurus trachurus (Linnaeus, 1758), Pagellus acarne (Risso, 1827), Scomber scombrus (Linnaeus, 1758)’tur. 2018 yılı ortalama BPUE 4,77 ± 0,85 kg.1000 m-1, 2019 yılı BPUE ise 3,20 ± 0,58 kg.1000 m-1 olarak hesaplanmıştır. Kasım ayı BPUE değerleri açısından en yüksek ortalamayı vermektedir. Ortalama BPUE 0 ile 19,1 kg.1000 m-1 arasında (ortalama: 7,97 ± 2,83 kg.1000 m-1) değişmiştir. İstatistiki olarak aylar arasında BPUE değerleri bakımından önemli bir fark vardır (Kruskal-Wallis test, p < 0,05).

Anahtar Kelimeler

Kupes, küçük ölçekli balıkçılık, hedef-dışı av, Güllük Körfezi

Destekleyen Kurum

Aydın Adnan Menderes Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Birimi

Proje Numarası

17002

Teşekkür

Yazarlar, finansal destekleri için Aydın Adnan Menderes Üniversitesi Bilimsel Araştırma Projeleri Koordinatörlüğü birimine [Proje No: BOMYO-17002] teşekkür ederler.

By-catch ratios from the bogue (Boops boops) gillnet fishery around the sea-cage fish farms in Güllük Bay (Aegean Sea)

Öz

This study aims to reveal the by-catch rates for gillnet fishery, targeted Boops boops by small-scale fisheries around fish farms in Güllük Bay (Aegean Sea), and to determine the by-catch per unit effort (BPUE) rates. The study was carried out through deck sampling at Göltürkbükü, Gündoğan, Yalıkavak, and Torba fishing ports during two seasons between November and April (2017-2018 / 2018-2019). A total of 147 fishing operations from 13 boats were randomly monitored. In gillnet fishing for bogue, a total of 18163 kg of the catch was caught from 48 species belonging to 30 families, including invertebrates. The target Boops boops was the most common species with a rate of 91.9%, of which 8.1% was determined as a by-catch. The most caught by-catch species are Diplodus annularis (Linnaeus, 1758), Scomber colias (Gmelin, 1789), Trachurus trachurus (Linnaeus, 1758), Pagellus acarne (Risso, 1827), Scomber scombrus (Linnaeus, 1758). While the average BPUE was 4.77 ± 0.85 kg.1000 m-1 in 2018, it was 3.20 ± 0.58 kg.1000 m-1 in 2019. November gives the highest average in terms of BPUE values. The average BPUE ranged from 0 to 19.1 kg.1000 m-1 (mean: 7.97 ± 2.83 kg.1000 m-1). Statistically, there is a significant difference in BPUE values between the months (Kruskal-Wallis test, p < 0.05).

Anahtar Kelimeler

Bogue, small-scale fisheries, non-target catch, Güllük Bay

Proje Numarası

17002

Kaynakça

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