CPUE comparison of traditional crayfish fyke net rigged with knotted net and alternatively knotless net

Abstract

In this study, it is aimed to compare the yield and strength of the crayfish fyke rigged with knotless net with 210d/12 rope thickness with those of the traditional net material rigged with 210d/6 knotted net which is widely used in Turkey in fishing crayfish (Pontastacus leptodactylus, Eschscholtz, 1823). The study was carried out on a monthly basis between June 2017 and May 2018. In the study, a total of 300 fyke nets, equipped with 150 classical and 150 alternative nets, were used. The caught crayfishes were measured and weighted according to the fyke net they were caught in. A total of 3509 crayfish were caught, 1465 of which were caught with alternative fyke net and 2044 with traditional fyke net. Average CPUE value ranged from 10.93 (g/fyke net/day) to 281.14 (g/fyke net/day) for per fishing operation. Average CPUE value of the traditional gear was found to be 98.34 (g/fyke net/day) , while that of the alternative gear was determined as 79.46 (g/fyke net/day), and no statistically significant difference was found between average CPUE values (p>0.05). Average strength value of the traditional fyke net was determined as (± SE) 10.43 ± 0.27 kg, while that value in 210d / 12 knotless net was identified as 14.50 ± 0.91 kg (p<0.05). Although it has high strength, since the CPUE value of the alternative fyke net is lower by 19.20% compared to the traditional gear, it is believed that its use in crayfish fishing will not be profitable.