This may occur in water as shallow as 10 m. Eggs hatch after 2 or 3 months, depending on water temperatures. Young squid grow rapidly. They are initially found in the surface plankton until they grow to about 4 cm. Adult size is typically 20 cm.
Males are larger.
Squid may become mature at 1 year of age and live less than 2 years. Mating consisting of the transfer of sperm from the male to the female may occur throughout the year, principally from February through August. Spawning consisting of the internal fertilization of the eggs and the deposit of the egg cases on the substrate may occur at a separate time of the year. Adult squid die following spawning. Species Interactions Opal squid are predators on pelagic fish such as herring, anchovy and sardine.