Trap catch of the red queen crab Chionoecetes japonicus when the giant medusa Nemopilema nomurai served as trap bait

Whether the by catch of giant medusa (Nemopilema nomurai) is served as a bait for red queen crab (Chionoecetes japonicus) traps or not, comparative fishing operations with commercially used traps were conducted off Kasumi, Hyogo in the Japan Sea in July 2004. Catches with fish bait (mackerel: conventional bait) were compared with catches with giant medusa bait Average catch number per trap were 19 and 6 individuals for male and female crabs respectively, while giant medusa bait traps caught few crabs. As a countermeasure for the by catch of giant medusa landed, we need to try to utilize it in crudity.