Longlining is a prevalent fishing practice utilized worldwide in fisheries that vary from small-scale operations to large and highly modernized industrial enterprises. An estimated 10 billion longline hooks are deployed globally every year.
Essentially a multifilament or monofilament mainline that varies in length from a few kilometers to 130 km (81 miles) or more is deployed from the fishing boat.
Attached to the mainline are branch lines that bear baited hooks, up to around 3,000 in total.
Boat and longline then drift for 1–24 hours allowing the lines to fish until the mainline is hauled back on board.