| Remarks |
Off Hawaii, occurs between depths of 100 and 850 m; in daytime it concentrates at 500 to 700 m (range 355 to 850 m) and vertically migrates at night to depths of 100 to 500 m with 85% concentrated at 150 to 300 m. In the northwestern Pacific transitional warm core rings and cold water, this species is a non-migrant, remaining below 400 m. Analysis of stomach contents from sperm whales off Japan suggests that mature females occur in a dense aggregation adjacent to an isolated oceanic rise. This species is extremely important prey for sperm whales and other odontocete whales, including short-finned pilot whales and Hubb’s beaked whale. Other predators include blue sharks in the northwestern Pacific. It is reported from the stomachs of swordfish off the west coast of Baja California, Mexico. Analysis of the dimorphic eyes suggests that the large left eye points upward and the small right eye points ventrolaterally when the animal is in its normal oblique, arms downward, position. This enables the squid in its daytime depth of 500 to 700 m, to use its large eye to utilize the dim daylight from above, while the small right eye perceives bioluminescent light from the side and below (Ref. 97142). |