Estimates of vital rates and population dynamics parameters of interest for blue sharks in the North and South Atlantic Ocean

Estimates of vital rates and population dynamics parameters of the North and South Atlantic stocks of blue shark (Prionace glauca) for potential use as inputs into production and integrated stock assessment models were computed based on biological information gathered at the 2023 Data Preparatory meeting. Six methods were used to compute deterministic estimates of rmax and a Leslie matrix approach was also used to incorporate uncertainty in growth parameters, the maturity ogive, fecundity, natural mortality, and lifespan by assigning statistical distributions to these biological traits. Productivity (rmax) estimated with the Euler-Lotka deterministic method using a length-based mortality estimator was 0.283 yr-1 (North); 0.142 yr-1 (South) and increased to 0.386 yr-1 (North) and 0.291 yr-1 (South) when using the mean of six life-history invariant mortality estimators. Productivity estimated with the stochastic Leslie matrix was very similar to that estimated with the deterministic method using the mean of the six M estimators: rmax=0.385; 95% CI: 0.224-0.596 (North); rmax=0.299; 95% CI: 0.165-0.389 (South). The corresponding values of steepness were h=0.86, 95% CI: 0.57-0.96 (North); h =0.80, 95% CI: 0.46-0.93 (South).