Haesung Enterprise Co., Ltd says that longline caught fish can be worth more than fish caught by other methods, however, despite this advantage, the fishing gear style should vary depending on target and depth.
Surface longline style is preferred by fishermen around the South Pacific Ocean for relatively cheap albacore fishing. But in order to catch more valuable fish for sashimi, such as bigeye and yellowfin, fishermen need to put their longline fishing gear deeper - around 400-500m depth. In order to implement this deep fishing style, fishermen need to put something heavy on the whole branchline unit.
The prototype method has been to use heavy polyester ropes, to put lead sinkers, or to put snap or swivels with lead sinkers, but this creates more work for the fishermen and also creates more contamination in the ocean. If the whole branchline does not sink fast enough to the target, some of the bait can be taken by seabirds, and some branchline may be swung aside by strong tides and currents far from the target position.
Haesung Enterprise Co., Ltd. began producing Tetron cord in 2008, which was originated by the Japanese longline fishing style. The construction of Tetron cord is 16 braided poly-monofilament (luminous treated) that is heavier than nylon by 22%. Inside the braided poly-monofilament, coated lead core lines makes this cord heavier. Haesung says that outside coating treatment of lead core helps reduce contamination of the ocean. Well-braided construction increases the breaking strength by more than 200kg, which is enough for bigeye and yellowfin tuna. And it is also heavier than nylon.
Haesung says that Tetron is a good solution for fishermen looking for heavy fishing gears for deep sea longlining. Jointing can be done simply by crimping aluminum sleeve. Fishermen can combine the whole branchline with a nylon monofilament fishing line. And luminous treated poly-mono may lure the fish to the hooks in the deep dark sea.
