Individual-based modelling to fine-tune management measures for commercial demersal sharks

Abstract

Individual-Based Models (IBMs) can be used to study population dynamics by emphasising individual variability in life-history traits and behaviour. Here, we built a zero-dimensional IBM to describe the population dynamics of smooth-hound sharks (Mustelus spp.) living in the northern Adriatic Sea, a highly exploited basin of the Mediterranean Sea. We integrated the density-dependence of individual-level processes based on bioenergetic theory with the explicit consideration of the intra-specific variability of life cycle processes into the model. The individual-based approach allowed us to investigate population status, highlight and fill knowledge gaps in the biology of the species, and test the potential effectiveness of innovative conservation measures. Although IBMs are a complex and potentially data-intensive methodology, this work demonstrates their usefulness as screening tools to systematically identify and select, within a pool of options, promising fisheries management measures for elasmobranch conservation and sustainable exploitation.