Effect of Different Baits on Catch Per Unit Effort (CPUE) for Catching Narrow-Clawed Crayfish (Pontastacus leptodactylus) with Fyke-Nets and Traps in Çanakkale Atikhisar Reservoir

Abstract

This study was aimed to determine the effects of different bait types on the efficiency of fyke-nets and traps in catching narrow-clawed crayfish (Pontastacus leptodactylus (Eschscholtz, 1823)). The study was carried out in Atikhisar reservoir, Çanakkale, between July 2020 and March 2021. In the study, 12 traditional fyke-nets (“D” inlet, 5 rigid rings and a leader net) and 12 traps (double inlet) were used. Fyke-nets and traps were rigged with 34 mm stretched mesh that are commonly used in crayfish fishing in Türkiye. Three different bait types including fish, chicken and bread and a control treatment with no bait were allocated to each gear type. Baits were distributed randomly to each gear before fishing trials. The baits were placed in small bags corresponding to 1% of total trap volume. The results of 24 trials showed 68.8% (1940 crayfish) of the total catch was caught with fyke nets and 31.20% (880 crayfish) with traps. The highest average CPUEN values for both trap types were observed in those baited with the chicken meat which were 7.89±1.02 n/fyke net/day and 5.07±0.88 n/trap/day.. The mean length of the crayfish caught by the fyke nets was significantly smaller than those caught by the traps (p<0.05). When the mean CPUE values based on the number of fishing operations were compared, differences were significant for baits other than the chicken meat (p<0.05). These results showed that catching efficiencies of baited fyke-nets and traps were higher (especially chicken meat) than those of unbaited traps than those without bait.

Keywords

• crayfish
• fyke-net
• trap
• bait
• catch per unit effort (cpue)