Survival of fish after escape from a 40 mm stretched diamond mesh trawl codend in the Aegean Sea


  • Faik Ozan Düzbastilar Ege University, Centre of Underwater Research and Application
  • Celalettin Aydin Ege University, Fisheries Faculty
  • Gülnur Metin Ege University, Fisheries Faculty
  • Altan Lök Ege University, Centre of Underwater Research and Application
  • Ali Ulaş Ege University, Centre of Underwater Research and Application
  • Aytaç Özgül Ege University, Centre of Underwater Research and Application
  • Benal Gül Ege University, Fisheries Faculty
  • Cengiz Metin Ege University, Centre of Underwater Research and Application
  • Hüseyin Özbilgin Mersin University, Fisheries Faculty
  • Tuğçe Şensurat Ege University, Graduate School of Natural and Applied Sciences
  • Adnan Tokaç Ege University, Fisheries Faculty



survival rate, escapes, trawl codend, discard and by-catch, Aegean Sea


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.


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How to Cite

Ozan Düzbastilar F, Aydin C, Metin G, Lök A, Ulaş A, Özgül A, Gül B, Metin C, Özbilgin H, Şensurat T, Tokaç A. Survival of fish after escape from a 40 mm stretched diamond mesh trawl codend in the Aegean Sea. Sci. mar. [Internet]. 2010Dec.30 [cited 2024Feb.25];74(4):755-61. Available from: