Age and growth of two smoothhound shark species from the eastern Central Pacific Ocean

Context. Understanding age and growth is fundamental for fisheries management, yet these parameters remain unestimated for Mustelus lunulatus and M. henlei in the Ecuadorian Pacific, limiting population assessments and management efforts. Aims. To estimate the age and growth parameters of M. lunulatus and M. henlei in the Ecuadorian Pacific. Methods. Vertebrae from 129 M. lunulatus and 164 M. henlei were sectioned for age estimation. Length-at-age data were analysed using von Bertalanffy, Gompertz, and Logistic models under Bayesian and frequentist approaches. Key results. Bayesian analysis showed the Gompertz model best fit M. lunulatus (combined sexes and females), while the von Bertalanffy model fit males. For M. henlei , von Bertalanffy was optimal across all groups. Model selection was based on the leave-one-out information criterion (LOOIC). Conclusions. Both species exhibited moderate growth rates and relatively small asymptotic sizes compared to other shark species. Implications. The information presented here has important implications for fisheries management, as it can be incorporated into future population models to improve assessments and conservation strategies.