By-catch reduction of skate and ray species in the bottom trawl

In this thesis study, it is aimed to eliminate the stingray species, which are very important for marine ecosystem and also critical situations in the IUCN red list. İn the bottom trawl hunting they are often discarded and landed very low. This study aimed they were to be thrown out of the net before going to the trawl net using the Supershooter model TED grid. In the field studies carried out with "R/V Akdeniz Su" vessel, which belongs to Akdeniz University, 2 different escape openings were tried and a total of 29 valid trawl hauls were made. The supershooter model TED grid, which was used to reduce non-target ray and skate hunting in the bottom trawl net which is in the aim of this thesis study, missed 14 out of 16 fishes in the bottom-escaped hauls, and these 14 individuals were 97% of the total weight of the hunt. 39 out of a total of 83 fishes have escaped from the top-escaped hauls, but this constitutes 87.38% of the total weight in terms of 39 individuals.On the other hand, when we look at the effect of the use of TED grid on the commercially important species in the trawl net, it was recorded that a reduction of 26.56% by weight in the bottom-escaped hauls resulted in a decrease of 39.13% in the top-escaped hauls. In addition to stingrays, important culverts such as C. Caretta and wastes such as car wheels have been found to be thrown out of the trawl net via the grid. As the results of the measurements and the graphs show, the use of Supershooter TED grid model has been found to be successful especially for the removal of large stingray individuals from the trawl net.