The digestive system of 36 paralarvae and 150 juvenile Dosidicus gigas were analysed to determine the diet. The early life stages were collected in the central and south region of the Gulf of California during different years and ranged in dorsal mantle length (ML) from 2.8 to 120.5 mm. The food content was separated first into identifiable material (IM) and non-identifiable material (NIM). All paralarvae contained only NIM stored mainly in the caecum rather than stomach. Juvenile squid feed on nine different prey types: euphausiids, copepods, amphipods, unidentified crustaceans, fishes, cephalopods, pteropods, bivalves and polychaetes. The IM were found mainly in the stomachs of juveniles with increasing number and diversity of prey in a function of increasing squid body size. In fact, juveniles from 60 to 120 mm ML had high stomach fullness percentages in half full and completely full stomachs suggesting improvement of swimming and hunting behaviour as they grow.
