A Record-Sized Whiting (Merlangius merlangus Linnaeus, 1758) Reveals Long-Term Size Decline in the Black Sea

Abstract

ABSTRACT This study documents an exceptional specimen of whiting (Merlangius merlangus) from the southeastern Black Sea and examines long-term changes in body size reported in the literature. A single specimen was captured off Tirebolu (Giresun, Türkiye) at a depth of 84 m using hook-and-line fishing. The fish measured 57.0 cm total length, weighed 2162 g, and was estimated to be 18+ years old based on sagittal otolith examination, representing the largest and one of the oldest verified individuals reported from Turkish waters. A review of published studies revealed a marked long-term decline in the mean body size of Black Sea whiting over the past three decades. Mean total length decreased from approximately 20–22 cm in the late 1980s to 11.44 cm in recent years, with regression analysis indicating a significant negative relationship between sampling year and body size (R² = 0.731, P < 0.001). The occurrence of this exceptional individual contrasts sharply with the current size structure of the population, which is increasingly dominated by smaller and younger fish. These findings suggest that sustained fishing pressure has progressively truncated the population size structure through the selective removal of older age classes. This record highlights both the historical growth potential of M. merlangus and the importance of conserving large, old individuals for maintaining stock resilience and sustainable fisheries management in the Black Sea. Keywords: Merlangius merlangus; Black Sea; maximum size; age record; body size decline; fisheries management.

Keywords

• Merlangius merlangus
• Black Sea
• maximum size
• age record
• body size decline
• fisheries management

Supporting Institution

No funding was received from institutions or agencies for the execution of this research

Project Number

none

Ethical Statement

No ethics committee permissions is required for this study

Thanks

The authors are grateful to the commercial fishermen Mehmet Elevlioğlu and Ömer Altun for capturing and providing the exceptional Merlangius merlangus specimen used in this study. Their support and collaboration are greatly appreciated.

Rekor Boydaki Bir Mezgit (Merlangius merlangus Linnaeus, 1758), Karadeniz'de Uzun Dönemli Boy Küçülmesini İfade Ediyor

Abstract

ÖZET Bu çalışmada, Güneydoğu Karadeniz'de yakalanan sıra dışı büyüklükte bir mezgit (Merlangius merlangus) bireyi rapor edilmekte ve literatür verileri kullanılarak türün uzun dönemli boy değişimi değerlendirilmektedir. Birey, Giresun'un Tirebolu açıklarında 84 m derinlikte olta ile avlanmış, 57,0 cm toplam boya ve 2162 g ağırlığa sahip olduğu belirlenmiştir. Sagittal otolit incelemesine göre bireyin yaşı 18+ yıl olarak tahmin edilmiş olup, bu değer Türkiye karasularından bildirilen en büyük ve en yaşlı doğrulanmış mezgit kayıtlarından birini oluşturmaktadır. Literatür incelemesi, Karadeniz mezgit stoklarında son otuz yılda ortalama vücut boyunda belirgin bir azalma olduğunu göstermiştir. Ortalama toplam boy, 1980'li yılların sonunda yaklaşık 20–22 cm iken son yıllarda 11,44 cm'ye kadar düşmüş; regresyon analizi örnekleme yılı ile ortalama boy arasında anlamlı negatif bir ilişki olduğunu ortaya koymuştur (R² = 0,731; P < 0,001). Günümüzde popülasyonun ağırlıklı olarak küçük ve genç bireylerden oluşması, bu olağanüstü bireyin istisnai niteliğini daha da belirgin hale getirmektedir. Bulgular, uzun süreli avcılık baskısının yaşlı ve iri bireylerin seçici olarak stoktan uzaklaştırılması sonucu popülasyonun boy yapısında önemli bir daralmaya neden olduğunu düşündürmektedir. Bu kayıt, mezgitin Karadeniz'deki tarihsel büyüme potansiyelini ortaya koyarken, büyük ve yaşlı bireylerin korunmasının stokların sürdürülebilirliği açısından önemini de vurgulamaktadır. Anahtar sözcükler: Merlangius merlangus; Karadeniz; maksimum boy; yaş kaydı; boyundaki küçülme; balıkçılık yönetimi

Keywords

• Merlangius merlangus
• Karadeniz
• maksimum boy
• yaş kaydı
• boyundaki küçülme
• balıkçılık yönetimi

Project Number

none

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