Live Jellyfish-baited Small-scale Traditional Trap Fishery Operated off the Eastern Coast of Sri Lanka

Abstract

The jellyfish-baited trap fishery was studied at four fishing grounds off the eastern coast of Sri Lanka throughout the entire fishing season (February and March) in three consecutive years, from 2017 to 2019, due to its uniqueness of export-oriented small-scale fishery. The composition of catch and their respective stomach content analysis revealed that the highly expensive Malabar groupers, which are predominantly targeted for export markets get attracted to traps as the secondary catch because they predate on the primary catch, e.g ., filefishes, rabbitfishes, surgeonfishes and triggerfishes, and the bycatch, i.e ., angelfishes and butterflyfishes. The varieties of primary catch are attracted to the jellyfish-bait. Among the 24 species of fishes caught, medusivorous Siganus javus had the highest abundance (24%), followed by Acanthurus mata (21%). Family-wise, the maximum contribution to the total catch was by Siganidae (56%), followed by Acanthuridae (34%). The average CPUE (kg three-man group-1 boat-1 day-1) ± SD of primary, secondary and by-catch during the fishing season was 87.0 ± 18.4 kg (~80%), 15.1 ± 3.4 kg (~14%) and 6.3 ± 1.4 kg (~6%) respectively, while the average total catch per trap was 7.2 ± 1.4 kg. The results of this study are important for utilizing the commonly available jellyfish bait to expand this trap fishery as well as to adapt the strategies for similar fisheries.