Posted by Mike Crispino
1 November 2012
In a recent blog post, the authors of a study on FADs & bycatch wrote that “After the sustainability of tuna stocks, the most pressing issue facing the commercial fishing industry is the management and mitigation of bycatch of non-target species.” Digging a bit deeper, the numbers show that 81-95% of bycatch is made of non-commercial tuna and bony fish, all considered to be fast growing with early sexual maturity and high fecundity.
Aside from small fish, two species of sharks are taken as bycatch in FAD fisheries – silky sharks (Carcharhinus falciformis, Carcharhinidae) and oceanic white tip sharks (C. longimanus, Carcharhinidae), with roughly 90% of the sharks captured being silky.
I thought it would be interesting to take the data from the study and illustrate how shark bycatch stacked up on two fronts – against shark bycatch in FAD-free fisheries and from ocean region to ocean region. Take a look:
When you look at the infographic keep in mind that 73% of the world’s tuna comes from the Pacific, where there is marginal difference in the bycatch of sharks among FAD and FAD-free fisheries.
But as the study makes clear, although purse seine fishing on FADs is not responsible for the major fishing mortality of silky and oceanic white tip sharks, research efforts to limit their mortality in FAD fisheries is needed and improved RFMO measures should be put in place as more is learned.