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This study aimed to determine the survival rates of three fish species, the brown comber (Serranus hepatus), black goby (Gobius niger) and annular seabream (Diplodus annularis), after their escape from a 40 mm stretched diamond mesh polyethylene (PE) codend. Experiments were carried out in the eastern Mediterranean in September 2007 using a conventional bottom trawl with 600 meshes around the mouth. A constant 15 min towing duration was used for all hauls. The towing speed varied between 2.0 and 2.5 knots. Codend covers, supported by two hoops, were used to retain escaping fish. At the end of each haul, these covers were detached from the codend, fixed to the sea floor at depths of 19 to 28 m, and then observed by the divers for a period of seven days. On the eighth day, all of the covers were lifted up and the survivors and mortalities were counted and measured. The mean survival percentages of open codend and experimental cages were found to be 97.1% and 98.3% for brown comber, 69.0% and 77.2% for black goby, and 97.5% and 98.6% for annular seabream respectively. Keywords: survival rate, escapes, trawl codend, discard and by-catch, Aegean Sea. RESUMEN: Supervivencia de peces después de escapar de una red de arrastre con copo de 40 mm de malla romboidal en el mar Egeo.-Este estudio tuvo como objetivo determinar las tasas de supervivencia de tres especies de peces, cherna afanecada o merillo (Serranus hepatus), chaparrudo (Gobius niger) y raspallón (Diplodus annularis), después de escapar de un copo con mallas de 40 mm romboidales de polietileno (PE). Los experimentos fueron realizados en el Me-diterráneo Oriental, en septiembre de 2007 utilizando una red de arrastre de fondo convencional con 600 mallas alrededor de la boca. La duración estándar fue de 15 minutos de arrastre para todos los lances. La velocidad de arrastre varió entre 2.0 y 2.5 nudos. Los peces que escapaban del copo eran retenidos por un sobrecojo, el cual quedaba separado del copo mediante aros que facilitan el escape en buenas condiciones entre ambos paños. Al final de cada lance, las cubiertas del sobrecopo se separaban del copo y se fijaban al fondo del mar a profundidades entre 19 y 28 m y fueron observados por buceadores durante los siete días siguinetes. Al octavo día se contaron y midieron los sobrevivientes. Los porcentajes de supervivencia medios de control y en las jaulas experimentales resultaron ser del 97.1% y 98.3% para la cherna afanecada; 69.0% y 77.2% para el chaparrudo y 97.5% y 98.6% para el raspallón. Palabras clave: tasa de supervivencia, escapes, red de arrastre, descartes y capturas acompañantes, mar Egeo.

Summary:This study was performed off the southern coast of Yassıca Island in the İzmir Bay on the Turkish coast of the Aegean Sea to investigate the mortality of red mullet (Mullus barbatus, Mullidae) escaping through 40-mm square-mesh and 44-and 50-mm diamond-mesh codends attached to a conventional demersal trawl net. In total, 48 replicate experimental hauls were performed in the summer and winter of 2011 and 2012. Mean escape mortality for all hauls in winter (33.2%±6.51) was significantly higher (p<0.0001) than that in summer (26.5%±6.19). Furthermore, mortality was also highest among the smallest fish, particularly during winter. Irrespective of season, the escape mortality of red mullet was lowest from the 40-mm square-mesh codend (mean, 25.5%±4.58). These observations emphasize the importance of investigating the survival potential of escaping fish when considering the benefits of different selective devices in the management of a fishery.Keywords: escape mortality, bottom trawl, size-related mortality, seasonal variation, mesh size, mesh shape, Aegean Sea.Variación estacional en la mortalidad post pesca del salmonete (Mullus barbatus), capturado con arrastre de fondo en el mar Egeo Resumen: El estudio se llevó a cabo frente a la costa sur de la isla de Yassica en la Bahía de Izmir, costa turca del mar Egeo para investigar la mortalidad post captura del salmonete (Mullus barbatus, Mullidae) que escapa de las redes de pesca con copos de malla cuadrada de 40 mm, y romboidales de 44 y 50 mm acoplados a una red tradicional de arrastre demersal. En total, se realizaron 48 lances experimentales durante el verano e invierno de 2011 y 2012. La media de la mortalidad post captura para todos los lances en invierno (33.2%±6.51) fue significativamente mayor (p<0.0001) que en verano (26.5%±6.19). Además, la mortalidad fue más alta entre los individuos más pequeños, especialmente en invierno. Independientemente de la estación, la mortalidad post captura del salmonete fue inferior con el copo de luz de malla cuadrada de 40 mm (media, 25.5%±4.58). Estas observaciones ponen de manifiesto la importancia de la investigación de la supervivencia potencial de los peces que escapan de las redes de pesca a la hora de considerar los beneficios de distintos dispositivos selectivos en la gestión de una pesquería.Palabras clave: mortalidad post captura, arrastre de fondo, mortalidad dependiente de la talla, variación estacional, luz de malla, forma de la malla, mar Egeo.Citation/Como citar este artículo: Düzbastilar F.O., Breen M., Aydin C., Özbilgin H., Özgül A., Ulaş A., Metin G., Gül B., Lök A. 2017. Seasonal variation in mortality of red mullet (Mullus barbatus) escaping from codends of three different sizes in the Aegean Sea. Sci. Mar. 81(3): 339-349. doi: http://dx

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A specimen of the serpent eel, Ophisurus serpens, with a total length of 1917 mm was caught on 2 March 2014 by an angler on a boat off the coast of Karaburun, in front of the Sarpıncık lighthouse. This specimen is the second record for the

Summary This paper presents the results of an application of a new ultrasonic telemetry method for brown meagre, Sciaena umbra inhabiting an artificial reef (AR) in the northern Aegean Sea. The objective of the study was the use of Vemco Positioning System (VPS) methods to determine the short‐term movements from August to September 2013 of four brown meagre in an artificial reef site. All S. umbra disappeared from the VPS detection range after a variable number of days (1–19 days of continuous monitoring). It is assumed that they did not colonize the site and left the detection area. From the methodological point of view, the VPS proved to be a suitable tool to determine fine‐scale movements of reef species such as Sciaena umbra in artificial reef areas. In conclusion, this study should be considered very preliminary; it is also necessary to increase the number of tagged fish, with additional research on the behavior of reef species to better clarify these aspects. This study will serve as a source for future studies in that it provides data for the understanding of fish movements in artificial reefs.