Fisheries bycatch can result in significant biomass removal of protected and vulnerable species, leading to population decline and increased extinction risk. A principal role of marine protected areas (MPAs) is to prevent biodiversity loss, so it is important to test the ability of MPAs to mitigate bycatch. In a new paper authored by Heather Welch (NOAA, University of California Santa Cruz), Bob Pressey (Centre of Excellence for Coral Reef Studies), and April Reside (University of Queensland), the authors quantified spatially and temporally explicit interactions between seven vulnerable bycatch species and Australia’s Eastern Tuna and Billfish Fishery. They then evaluated the ability of the Commonwealth Marine Reserve Network to avoid these interactions. The analysis demonstrated that both the 2012 proclaimed and the 2015 panel-recommended zonings will have minimal impacts on bycatch reduction, due to marginal overlap between MPA zones that prohibit fishing and areas of historically high fisheries effort. These results highlight the need for threats to marine biodiversity to be incorporated directly into design of MPAs.
Analysis results can be explored at https://heatherwelch.shinyapps.io/etbf_bycatch_app/
The overlap between total Eastern Tuna and Billfish Fishery effort across the time-series (1998-2007) and waters protected from longlining subsequent to the time-series. Protected waters (green) are shown for the 2012 proclaimed zoning (a) and the 2015 panel-recommended zoning (b). Waters that were removed from the analysis are show in black cross hatch.