In this study, we used high-throughput sequencing of the bacterial 16S rRNA gene to investigate the spatial and temporal structure of krill microbiomes from the Scotia Arc between the years 2016 and 2018, in the seasons summer and autumn. Antarctic krill is a keystone species in the Southern Ocean and targeted by a fishery, yet there remain key knowledge gaps in our understanding of its population connectivity. Studies in the Indian Sector of the Southern Ocean suggest krill microbiomes are spatially structured and could be a useful proxy for understanding population connectivity, but before this can be used for management and conservation we need to understand spatial and temporal microbiome variation in the key krill fishery areas in the Scotia Arc.