Kelp forests are known globally as hotspots for macroscopic biodiversity. Norway has Europe’s largest population of kelp having a long tradition of exploiting wild populations of this natural resource. There is currently a lot of interest in the species, Saccharina latissima, to develop Norway’s kelp industry through large scale cultivation at sea. Kelp forests are however vulnerable to climate change, overharvesting and biofouling by epiphytes. Due to the importance of kelp to Norway’s bioeconomy, it is vital to fill current research gaps in relation to kelp forest ecosystems in order to use the resource sustainably. Bacterial and epiphytic algal communities have been shown to be important for the fitness of kelp hosts, with certain epiphytes improving fitness and others leading to a complete loss of biomass within populations. This study, that I will implement at the Institute of Marine Research (NO), will quantify the gene flow between populations of kelp forests of S. latissima. The community structure of epiphytic algae and bacteria will be described to determine if the host genotype or the environment determines their composition. Finally, the key taxa associated with environmental change that could be used as bioindicators to proactively monitor kelp populations and cultivation sites will be established. This interdisciplinary project integrates community ecology and population genomics with an ecosystems approach to investigate the complexity of interactions occurring between the different organisms in the kelp forest habitat. The personal goal of this fellowship is to gain in-depth training in the techniques required to study population genomics linked to microbiomes, which are increasingly being shown to play pivotal roles in the shaping and functioning of populations. The host is a leading institution for marine research and provides a unique training environment where academia works directly with the concerned industries and policy makers.