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The paper presents the first European records of the copepod (Crustacea, Calanoida, Diaptomidae) Skistodiaptomus pallidus in shallow eutrophic waters indirectly connected with the Weser River, Northern Germany. Its original distribution is in the Mississippi basin of the United States of America. It is probable that this species entered the Weser River via ship ballast.

This paper reports the range extension of Kyphosus vaigiensis in the northeastern (NE) Mediterranean. On 18 November, 2018, a single specimen of K. vaigiensis was caught in İskenderun Bay (36°45.6′ N, 35°40.8′ E) by a recreational fisherman and reported through a social media application. The specimen was identified using morphological and molecular methods. Its occurrence and distribution in the NE Mediterranean were investigated based on interviews with fishers.

Bu çalışmada, çipura (Sparus aurata) avcılığında kullanılan monofilament fanyalı uzatma ağlarında dört faklı göz genişliğinin seçiciliği araştırılmıştır (28, 30, 32 ve 34mm). Balıkçılık denemeleri Şubat 2005 -Mayıs 2006 tarihleri arasında İskenderun Körfezi'nde gerçekleştirilmiştir. Sparus aurata'nın seçiciliği, SELECT (Millar, 1992) metodu ile işleyen GİLLNET bilgisayar programı ile belirlenmiştir. Beş farklı model kullanılarak; normal location, normal scale, gamma, log-normal and bi-modal, kullanılarak eldeki verilere en uygun seçicilik eğrisi belirlenmiştir. En uygun model bi-modal fonksiyon olarak belirlenmiştir. Bi-modal seçicilik eğrisine göre elde edilen optimum boylar sırasıyla; 17.49cm, 18.74cm, 19.99cm ve 21.24cm'dir. Buna göre, minimum avlama boyu ile (17cm) karşılaştırıldığında 28, 30, 32 ve 34mm göz genişliklerindeki ağlar, İskenderun Körfezi'ndeki çipura stokları üzerinde herhangi bir av baskısı oluşturmamaktadır. Anahtar Kelimeler: Fanyalı uzatma ağı seçiciliği, Optimum ağ göz genişliği, İskenderun Körfezi, Sparus aurata * Correspondence to: Erhan AKAMCA, Çukurova Üniversitesi, Su Ürünleri Fakültesi, Bu çalışma Çukurova Üniversitesi Bilimsel Araştırma Projeleri tarafından SÜF2004BAP11 numaralı proje ile desteklenmiştir. Journal of FisheriesSciences.comAkamca ve ark., 4(1): 28-37 (2010) Journal abbreviation: J FisheriesSciences.com 29 Abstract:The selectivity of monofilament trammel nets used in catch of gilt head bream (Sparus aurata, Linneaus, 1758) in İskenderun Bay-TurkeyIn this study, the mesh selectivity of monofilament trammel nets used in catch of gilt head bream (Sparus aurata) was investigated using four different mesh sizes (28, 30, 32 and 34mm).Fishing trials were carried out in İskenderun Bay from February 2005 to May 2006. Selectivity on Sparus aurata was assessed using the SELECT method (Millar, 1992), implemented in the GILLNET software. Five different functional models; normal location, normal scale, gamma, log-normal and bi-modal were used to fit the selectivity curve to the catch data. It was shown that the bi-modal function was the best to fit the data. For the selectivity curves on the bimodal, the optimum lengths (100% retention probability for the 28, 30, 32 and 34mm mesh sizes) were obtained as 17.49cm, 18.74cm, 19.99cm and 21.24cm, respectively. Thus, considering the minimum allowable landing size (17cm), 28, 30, 32 and 34mm mesh sizes do not cause an over fishing on gilt head bream stocks in Iskenderun Bay, Turkey.