Food and Growth Adult swordfish are opportunistic feeders on squid, pelagic and demersal fishes, and crustaceans. They may utilize their bill to kill their prey - rising from beneath a school of fish, swinging the sword from side to side, then consuming the fish that were killed. Larvae swordfish feed primarily on fish larvae and zooplankton. Juveniles feed on squid and small fishes. Swordfish larvae, and presumably juveniles, are a common food of other fishes, including larger swordfish.
Adult swordfish have few natural enemies.
Known predators include sperm and killer whales and large sharks. Fish caught on the commercial fisheries are predominately 4-5 years old. Maximum age is thought to be 9 years. There is some evidence swordfish in the Pacific may have a slower growth rate and smaller maximum size than fish in the Atlantic. Females apparently grow to larger sizes than males.