Large-scale experiment shows that nylon leaders reduce shark bycatch and benefit pelagic longline fisheries

Catch rates of blue marlin, snake mackerel and sharks were lower when nylon monofilament leaders, instead of wire leaders, were used on pelagic longline gear but bigeye tuna and black marlin catch rates increased. (No effect on yellowfin). Nylon leaders also had higher bite-off rates than the wire leaders.
Field Studies:

Location	Fishing gear	Reduction technique	Bycatch species	Effect on bycatch species	Catch	Effect on target catch	Type
Northeastern Australia	Hooks-and-Lines	Alternative leader design	Sharks	Wire leaders had higher catch rates of sharks when compared to nylon monofilament leaders	Bigeye and yellowfin tuna	Nylon monofilament leaders had higher catch rates of bigeye tunas when compared to wire leaders, but had no effect on yellowfin catch	In the wild