As terrestrial organisms, we recognise immediately physical features like mountains and valleys, the presence of primary producers and their main limiting factor – water. We expect to find different upper trophic levels in different environments. However, to us the open ocean looks just a seemingly homogeneous extension of salty water. The situation however is different when we look at the ocean with satellite instruments, or when we track the displacements of marine organisms like seals, whales, and marine birds. In this talk I will discuss the case of the Kerguelen region (Indian sector of the Southern Ocean). By combining satellite data, nonlinear diagnostics, and ship-based data, I will attempt to link the physical dynamics to the distribution and behavior of the different levels of the trophic chain.