Türkiye Kıyılarındaki Küçük Ölçekli Balıkçılıkta Birim Çaba Başına Düşen Av Miktarının (CPUE) Mekansal ve Zamansal Değişimi

Abstract

Balıkçılığa bağlı birim çaba başına düşen av miktarı (CPUE) değerleri, balıkçılıktan bağımsız araştırmaların yüksek maliyeti nedeniyle stok bolluğunun değerlendirilmesinde önemli bir göstergedir. Bu çalışmada, Türkiye kıyılarındaki küçük ölçekli balıkçılığın (SSF) balıkçılık çabası ve CPUE değerlerindeki mekansal (Karadeniz, Marmara Denizi, Ege Denizi ve Akdeniz) ve zamansal (2016-2022) değişimlerin belirlenmesi amaçlanmıştır. SSF'ye yönelik uygulanan destek kapsamında Tarım ve Orman Bakanlığı'nın 2017-2023 yılları arasında tuttuğu kayıtlar retrospektif olarak incelenmiş ve analiz edilmiştir. Balıkçılık çabası (yılda balıkçılık gün sayısı) ve CPUE (kg/gemi/gün ve kg/kW/gün) değerleri tüm deniz ve segmentler (yıl ve deniz) için hesaplanmış ve istatistiksel karşılaştırmalar tek yönlü varyans analizi (ANOVA) ile yapılmıştır. Bu çalışma, Türkiye küçük ölçekli balıkçılığında CPUE hesaplamasına motor gücünü (kW) dahil eden ilk çalışmadır. Balıkçılık gün sayısında 2016-2022 yılları arasında 32 gün azalma olmuş, yıllar ve denizler arası farklar istatistiksel olarak anlamlı bulunmuştur (p < 0,001). 2022 yılında tüm denizlerde 2016 yılına göre daha yüksek CPUE (kg/tekne/gün) değerleri elde edilmiştir (p < 0,05). Tüm yıllarda en yüksek CPUE (kg/gemi/gün) değerleri Karadeniz'de, en düşük değerler ise Ege Denizi'nde elde edilmiştir (p < 0,001). Tüm denizler birlikte değerlendirildiğinde CPUE (kg/kW/gün) 2016 yılına göre 2022 yılında %7 azalmıştır. Balıkçılık gün sayısı önceki dönemlere göre daha düşük, CPUE (kg/gemi/gün) ise daha yüksektir.

Keywords

• Küçük ölçekli balıkçılık
• CPUE
• Karadeniz
• Ege Denizi
• Akdeniz
• Marmara Denizi

Spatial and Temporal Variation of Catch per Unit Effort (CPUE) in Small-Scale Fisheries Along the Turkish Coast

Abstract

Fishery-dependent catch per unit effort (CPUE) values are an important indicator for assessing stock abundance due to the high cost of fishery-independent research. In this study, it was aimed to determine the spatial (Black Sea, Sea of Marmara, Aegean Sea and Mediterranean Sea) and temporal (2016-2022) changes in the fishing effort and CPUE values of small-scale fisheries (SSF) along the Turkish coast. Records collected by the Ministry of Agriculture and Forestry between 2017 and 2023 within the scope of the support implemented for SSF were retrospectively examined and analyzed. The fishing effort (fishing days per year) and CPUE (kg/vessel/day and kg/kW/day) values were calculated for the whole sea and segments (year and sea), and statistical comparisons were made with one-way analysis of variance (ANOVA). This study was the first to include engine power (kW) in the calculation of CPUE in Turkish SSF. The fishing days decreased by 32 days from 2016 to 2022 and the differences between the years and between the seas were statistically significant (p < 0.001). While higher CPUE (kg/vessel/day) values were obtained in 2022 compared to 2016 in all seas (p < 0.05). The highest CPUE (kg/vessel/day) values in all years were in the Black Sea, and the lowest values were in the Aegean Sea (p < 0.001). The CPUE (kg/kW/day) for the whole sea decreased by 7% in 2022 compared to 2016. Fishing days per year was lower and the CPUE (kg/vessel/day) were higher compared to the previous periods.

Keywords

• Small-scale fisheries
• CPUE
• Black Sea
• Aegean Sea
• Mediterranean Sea
• Sea of Marmara

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