Broad impacts of fine-scale dynamics on seascape structure from zooplankton to seabirds

Abstract

In marine ecosystems, like most natural systems, patchiness is the rule. A characteristic of pelagic ecosystems is that their 'substrate' consists of constantly moving water masses, where ocean surface turbulence creates ephemeral oases. Identifying where and when hotspots occur and how predators manage those vagaries in their preyscape is challenging because wide-ranging observations are lacking. Here we use a unique data set, gathering high-resolution and wide-range acoustic and GPS-tracking data. We show that the upper ocean dynamics at scales less than 10 km play the foremost role in shaping the seascape from zooplankton to seabirds. Short internal waves (100 m-1 km) play a major role, while submesoscale (∼1-20 km) and mesoscale (∼20-100 km) turbulence have a comparatively modest effect. Predicted changes in surface stratification due to global change are expected to have an impact on the number and intensity of physical structures and thus biological interactions from plankton to top predators.