Catching efficiency of various hanging ratio and colour monofilament gill nets

ABSTARCTPhD ThesisCATCHING EFFICIENCY OF VARIOUS HANGING RATIO AND COLOURMONOFILAMENT GILL NETSBülent ORSAYFırat UniversityGraduate School of Natural and Applied ScienceDepartment of Fish Catching and Fish Processing Technology2007, Page: 77This study was conducted at 8 different stations in Çemişgezek fishing cooperative area ofKeban Dam Lake from September 2004 to April 2006.In study, in order to determine fish catching efficiency of colored gillnets with 40,55,70 mmmesh size in Keban Dam Lake and to stained green, blue, red, black color from each mesh sizes, 4different color nets with hanging ratio of 0,50 and 0,67 from each mesh sizes seperate to equip 24number nets were used.During two years study period, in total 1169 fish were caught; of these 606 with hanging ratioof 0,50 and 563 with hanging ratio of 0,67 with monofilament gill nets.According to hanging ratio, mesh size and color, of nets total lenght and weight measured ofthese avarege and standart error were calculated. Therefore, Chi-square analyesis was used in comparethis fishes.In this study was determined that different colors of material effect on catch efficiency in gillnets. Nets with 0,50 hanging ratio and 40 mm mesh size catched Capoeta trutta while green and blackcolor nets with 0,50 hanging ratio and 55 mesh size catched Barbus rajanorum mystaceus andCapoeta trutta. Black color net with 0,67 hanging ratio and 40 mm mesh size catched Capoeta truttamorely while blue color with 0,67 hanging ratio and 55 mm mesh size catced Barbus. esocinus andBarbus xanthopterus.The results showed that material of different colors is effective on gillnets and it should beblack, red, green and blue gill nets for black fish, carp, earring fish and barbel fish respectively inÇemişgezek area of Keban Dam Lake.Key Words: Keban Dam Lake, Colored gill net, Hanging ratio, Monofilament