Scorpaena porcus is one of the most important members of rock and reef community in the Black Sea. The present study aimed to investigate the bio-ecological properties of S. porcus in the Eastern Black Sea. The growth, age, and sex compositions, feeding and reproduction biology of 1061 individuals were examined. The total length of the individuals ranged between 6.7 and 25.5 cm. The observed age ranged up to 8 years in both the sexes; the oldest individual both in males and females was 8 years of age. The von Bertalanffy growth function parameters in the samples were L∞=22.15 cm, k=0.287, t0=-1.577 (year) and W∞=238.14 g. The sex ratio (male/female) was 1/1.13. S. porcus fed most frequently on fish and decapods in all seasons. The reproduction period was identified to be between June and October, as evident by GSI values and macroscopic and histological analysis of gonads. Hydrated oocytes first appeared in June on the histological examinations; however, the atresia was highest in October. In conclusion, the study identified S. porcus as a new target species and the studied bio-ecological characteristics are expected to be important in developing an optimal strategy for fishery stock management.

Bottom trawl fishery is carried out intensively throughout the season in the Black sea. For this reason, the selectivity effects of five codend with different mesh size, shapes and escape panels (commercial (40D), 50 mm diamond-shaped (50D), and 40 mm square-mesh (40S) and radial square mesh escape panels (RSEP) which were added to the front and back section of 40D) were investigated. Using a commercial fishing trawl, 44 valid hauls were carried out from August 23 rd to October 24 th 2016 on the Sakarya coast to the South west of the Black Sea. The L50 value of commercial cod end was calculated as was 12.9 cm for Mullus barbatus (red mullet), and was improved in cod ends with RSEPs. Further, the L50 values obtained from the other cod ends were found to be very high (40S: 15.62 cm, 50D: 15.24 cm). It was noticed that none of the cod ends showed sufficient selectivity for bluefish (Pomatomus saltatrix), which was caught as bycatch. The comparative account of the findings of current study with the previous studies advocates that the cod ends need to be made from PA netting and RSEP should be applied for more escape area.