Derive growth parameters and natural mortality rates for krill considering spatial heterogeneity in Subarea 48.1

The Western Antarctic Peninsula ecosystem plays a critical role in the cycle life of Antarctic krill (Euphausia superba). Recent environmental changes and increasing exploitation in this area have led to alterations in the structure of the krill population, calling for a review of the management approach. In this study, we derive growth parameters and natural mortality rates for krill while considering spatial heterogeneity in the Western Antarctic Peninsula. We use Modal Progression Analysis (MPA) to estimate L_inf, and K for each management stratum in Subarea 48.1. Subsequently, we calculated natural mortality (M) for each stratum using bioanalytical methods. This study identified variations in krill's life history traits across different locations. These findings can be incorporated into management strategies and recommendations when analyzing population dynamics models for krill. This study underscores the importance of accounting for spatial heterogeneity in estimating krill life cycle parameters, which can significantly impact assessment models used to provide management recommendations to CCAMLR.