Swordfish eat fishes such as Atlantic mackerel, barracudinas, silver hake, redfish, herring and lanternfishes. They also eat squid. They hunt at many depths, from near the surface into deep water. A grown swordfish has no teeth, so it swallows its food whole, which limits the size of prey it can handle.

In a study of swordfish in the California Current, the diet consisted mainly of squid and other cephalopods, but it also included fishes from near the surface and from the deep. Another study found that most large fish prey had been slashed, while small prey items had been consumed whole. Together, the studies show a diet of squid and fish, and scientists think the sword leaves marks on the larger prey.

Swordfish range from about 60 degrees north to 45 degrees south. They tend to move to warmer waters in winter and cooler waters in summer, and some visit the Gulf of Maine in summer. In the western North Atlantic, swordfish are found in the Gulf Stream, extending north to the Grand Banks of Newfoundland.

Tagging shows how far they can go. In one tagging study, juvenile swordfish off the Azores kept to that area. Adults tracked in the western Atlantic migrated long distances between the Grand Banks and the Caribbean. NOAA says North Atlantic swordfish migrate thousands of miles each year. Researchers say swordfish commonly reach 10 feet, or 3 meters, in length. Swordfish live in oceans around the world and hunt at many depths, from near the surface into deep water.

Words to know

• cephalopods: squid and kin
• juvenile: young
• migrated: moved far