Since kicking off in 2024, the MARHAB work packages have employed cutting edge technology (genomics, tracking, in situ observations, machine learning) in state-of-art ecosystem research, in pursuit of scientific underpinnings needed to bring about the long overdue reconciliation of fisheries management with biodiversity conservation. To expand our understanding of biodiversity and connectivity in our study region (WP2) we have sampled pipefish, crabs and isopods from populations both in- and outside the Skagerrak. Genomic analyses are now under way. We have reviewed the knowledge on sand and gravel habitats (WP3), their ecological function and associated species. In MARHAB we study the habitat preference of sandeel (Ammodytes sp.), and its role in the food web. Biogenic reefs are essential marine habitats, and in MARHAB we study data poor habitats such as blue- and horse mussel reefs with underwater video to capture their function and the interacting, associated species. Top predators confer essential trophic function and spread such function though their mobility. MARHAB is tracking such movements (WP4) in fish and marine mammals. To test whether conservation- or fisheries management strategies are successful in promoting the function of top predators, MARHAB is using non-destructive monitoring techniques to study species assemblages and size distributions (WP5).