Set your longline deep: Catch more target fish and avoid bycatch by using a new gear design

Citation
SPC (2005) Set your longline deep: Catch more target fish and avoid bycatch by using a new gear design
Abstract

Even if longlines are set deep to target tuna and day swimming swordfish, many baited hooks still end up in the mixed layer where most bycatch occurs. Bycatch can be costly as: it takes time to handle unwanted or protected species appropriately; baits that are taken by bycatch are not available for target fish; gear is lost when sharks bite off hooks; there is the potential for fishermen to be injured when handling some unwanted species; and it is harmful to the ecosystem, wasteful, and could result in fishery closures. Set your longline so that all baited hooks are fishing deeper than 100 m, out of the mixed layer, and out of each of most bycatch. This will decrease bycatch and could increase target catch and profits.