Humboldt squid are found in the warm waters of the Eastern Pacific Ocean, and cover a range that expands as the waters are warmed by El Niño. These large squid migrate vertically (diel migration) to follow their prey, from depths of over 1,000m during the day to the surface waters at night. They capture their prey with their tentacles and suckers and rip it apart with their powerful beak. Like other cephalopods, Humboldt squid can change colour, flashing bright red when angered or excited - giving rise to their name 'the red devil'.