Development of formulated bait for edible crab (Cancer pagurus L.), using by-products from the fisheries and aquaculture industry

Four formulated baits for the edible crab (Cancer pagurus L.), were developed. In all baits, fish skin and saithe were the main ingredients. Fish skin gelatin strengthened by the enzyme transglutaminase functioned as a binder in all baits. In Bait 1, a meal mixture (shrimp meal, kelp meal, fish meal) was added as attractant. In bait 2, protein concentrate (PC; 15% to 30% dry matter on a dry matter basis >90% protein where of >50% collagen/gelatin) was added as an attractant in addition to the meals mixture used in bait 1. Blue mussels (Mytilus edulis) and cod (Gadus morhua) roe were used as attractants in Bait 3 and 4 respectively. During three field studies, the performance of the formulated baits were compared with that of the most commonly used natural bait, chopped untreated saithe (Pollachius virens). Traps baited with baits 1 and 2 had a significantly lower CPUE compared with traps baited with natural baits, whereas traps baited with baits 3 and 4 had a significantly higher CPUE compared with traps baited with natural bait.