Gel-form bait made from fish waste: Can be a potential alternative to commercial bait for handline fishing?

Abstract

The fillet wastes of Rainbow trout (Oncorhynchus mykiss), one of the most important species for mariculture in Türkiye, are only given to fish meal oil factories during the anchovy season. The rest of the time, they are thrown into the sea. This situation causes significant marine pollution problems and economic losses. The reuse of these wastes in the fishing industry by processing them with different methods is of great importance in terms of converting the waste into value added product and preventing marine pollution. To find a solution to this problem, gel-form baits were obtained by mixing protein hydrolyzate obtained from Rainbow trout viscera with glycerol and gelatin. It was then investigated whether these baits could be an alternative bait in commercial whiting (Merlangius merlangus) handline fishing. For this purpose, the catch efficiency of the commercially used handline and the handline with gel-form bait were compared. Sea trials were conducted under commercial operation conditions and within the borders of Rize between 3–24 October 2020. After a total of 11 days of sea trials, 91 operations were carried out for each tested bait. The findings show that the catch efficiency of the handline with gel-form bait is lower than the commercial one. Suggestions for the development of alternative bait were given in the discussion section.