Although there have only been a few sightings of the megamouth shark, it is believed that this species of shark likes to live in the open ocean. The sixth specimen found was tagged and followed for two days, allowing insight into its habitat preference and behaviour. It stayed at a depth of 15 metres during the night, then dove to 150 metres at dawn and returned to shallow waters at dusk. So the megamouth is presumed to be a vertical migrator on a 24 hour cycle, spending the daytime in deep waters and ascending to midwater depths at night. This vertical migration may be a response to the movements of the small animals on which it feeds. The krill that make up part of the megamouth's diet also migrate from deep waters to the surface.