An updated statistical catch-at-length assessment for Eastern Atlantic bluefin tuna

Butterworth and Rademeyer (2013) provided an initial Statistical Catch-at-Length (SCAL) assessment of the eastern populations of North Atlantic bluefin tuna. The primary purpose in fitting to length- rather than to age distribution data was to avoid the need to make use of the somewhat coarse cohort-slicing method to provide the latter. Here these analyses are updated using comparable inputs to those agreed for the initial 2014 updated VPA assessments. The results suggest a spawning biomass time series similar to that estimated by VPA over the 1975 to 2005 period, but lower after and appreciably higher before this period.