Download FAR 2016/60 Size, maturity and length composition of blue sharks observed in New Zealand tuna longline fisheries

Data and samples collected by observers were used to assess the catch composition of blue sharks caught in New Zealand waters. The catch was dominated by juveniles, with most sharks being shorter than 200 cm fork length, and an estimated 90% of males and 95% of females being immature. Vertebrae were examined whole or sectioned and X-rayed to estimate age, but growth bands were ambiguous and uninterpretable. It was impossible to develop an objective ageing protocol for New Zealand blue shark.