Assessment of the efficiency of Funnel net and Hokkaido traps for Astacus leptodactylus Eschscholtz, 1823 catching in ponds

Abstract

Various fishing tools have been used for catching Astacus leptodactylus in the world. In this research, a trap was specially designed for crayfish fishing with some changes in the shape and dimensions of the Hokkaido trap, and its efficiency was compared with Funnel net traps. Funnel and Hokkaido traps ​​were used in three mesh sizes of 2, 8, and 12 mm. 12 main courses (in every 4 traps) were placed in the pool in the same consecutive conditions. Traps were observed daily and fishing effort, length-weight relationship, and longitudinal classification were assessed. The sex ratio (male to a female) in Hokkaido traps was 1: 1.01 and in funnel net was 1: 1.04. The mean length and weight of the crayfish’s in Hokkaido traps were 116.1 mm and 54.67 g and in funnel traps were 105.96 mm and 42.14 g. CPUE in Hokkaido traps was 2.77 and in funnel traps were 2.07 per 24 hours. The length-weight relationship in Hokkaido traps was W=3E-05L3.02 and in funnel traps were W=3E-05L2.98. The results of this study showed that Hokkaido traps were more efficient in crayfish catching and perform more effectively in catching larger ones.

Keywords

• cpue
• funnel net
• hokkaido traps
• astacus leptodactylus.