Simon M. auteur aut IRD Fromentin J. M. auteur aut IRD Bonhommeau S. auteur aut IRD Gaertner Daniel auteur aut IRD Brodziak J. auteur aut IRD Etienne M. P. auteur aut IRD text journalArticle eng text/pdf reformatted digital access The intrinsic population growth rate (r) of the surplus production function used in the biomass dynamic model and the steepness (h) of the stock-recruitment relationship used in age-structured population dynamics models are two key parameters in fish stock assessment. There is generally insufficient information in the data to estimate these parameters that thus have to be constrained. We developed methods to directly estimate the probability distributions of r and h for the Atlantic bluefin tuna (Thunnus thynnus, Scombridae), using all available biological and ecological information. We examined the existing literature to define appropriate probability distributions of key life history parameters associated with intrinsic growth rate and steepness, paying particular attention to the natural mortality for early life history stages. The estimated probability distribution of the population intrinsic growth rate was weakly informative, with an estimated mean r = 0.77 (+/-0.53) and an interquartile range of (0.34, 1.12). The estimated distribution of h was more informative, but also strongly asymmetric with an estimated mean h = 0.89 (+/-0.20) and a median of 0.99. We note that these two key demographic parameters strongly depend on the distribution of early life history mortality rate (M-0), which is known to exhibit high year-to-year variations. This variability results in a widely spread distribution of M-0 that affects the distribution of the intrinsic population growth rate and further makes the spawning stock biomass an inadequate proxy to predict recruitment levels. specialized ATLANTIQUE 040 7 10 e48583 2012 1932-6203 https://www.documentation.ird.fr/hor/fdi:010058206 10.1371/journal.pone.0048583 1932-6203 [F B010058206] https://www.documentation.ird.fr/hor/fdi:010058206 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers17-09/010058206.pdf IRD - Base Horizon / Pleins textes 2013-02-06 2017-10-03 fdi:010058206 fre