Improved growth estimates from integrated analysis of direct aging and tag-recapture data: An illustration with bigeye tuna (Thunnus obesus) of the eastern Pacific Ocean with implications for management

摘要

The growth modeling framework to integrate age-at-length and tag-recapture length-increment data sources is well established in fishery science. Surprisingly, the use of the so-called "Laslett-Eveson-Polacheck (LEP)" statistical approach has been infrequent since its development in the early 2000s. Likely, this is due to the complex treatment of process error by the methodology and its resulting high computational demands. Using bigeye tuna in the eastern Pacific Ocean as an example, this research presents a modified LEP method to strengthen the benefits of integrating the two sources of data into a single-step modeling approach. The bigeye tuna case study is typical in the tuna world in which age estimates from direct otolith readings commonly cover the young segment of the species life-cycle only, causing growth model predictions extrapolated beyond the data to be unreasonably high and contain uncertain values of the asymptotic length parameter L-infinity.