Many types of marine life congregate for protection and migrate between areas, creating an opportunity for resourceful predators to find food. But it’s only recently that scientists have been able to reliably observe the movement of large populations of fish, also called shoals, that would allow us to see these floating buffets in real time. Using a sonar-based technique called Ocean Acoustic Waveguide Remote Sensing, or OAWRS, oceanographers in Norway and at MIT were able to record one such buffet.