Download AEBR 354 Spatial risk assessment for selected shark species in New Zealand – Part I: pelagic bycatch

This report describes application of a novel risk assessment approach to pelagic bycatch (non-target) shark species. The assessment estimated the exploitation rate inflicted on each of six species by fishing in the New Zealand Exclusive Economic Zone. All relevant fishing methods were included so that the total fisheries impact could be gauged. The exploitation rate is a measure of the proportion of the selected population numbers that are killed as a result of fishing, and includes those individuals that die even when returned to the ocean. The exploitation was compared to a theoretical productivity measure to estimate whether it was high enough to inflict long-term damage on the population. Thresher shark (Alopias vulpinus), porbeagle (Lamna nasus) and mako shark (Isurus oxyrinchus) were identified as being at higher risk from fishing and risk for the protected basking shark (Cetorhinus maximus) and white pointer shark (Carcharodon carcharias) was lower but still non-negligible.