A swordfish's life begins as one of an enormous number of eggs: a female swordfish may carry from 1 million to 29 million eggs, and the eggs are fertilized outside the mother's body. Solitary males and females appear to pair up during the spawning season, and young swordfish hatch about 4 millimeters long and live near the surface. The young have scales, but they lose them by the time they are about 3 feet, or 1 meter, long, and a grown swordfish has no scales at all. Swordfish reach adulthood and can have young at 5 to 6 years old. Swordfish live in oceans around the world. The egg count is a range rather than a single number, which is a reminder that the figures reported about swordfish are estimates with limits.
How old is an old swordfish? As of November 2026, swordfish live about 9 years, but it is hard to tell a swordfish's age because its ear bones are very small and adults have no scales. The numbers for maturity also differ: NOAA says females can reproduce between 4 and 5 years old, while the Florida Museum says swordfish reach maturity at 5 to 6 years. Size is counted as well as age. A swordfish can grow to about 177 inches long as of November 2026, from the tip of its bill to the end of its tail, and the largest published weight for a swordfish, as of November 2026, is 650 kilograms, about 1,400 pounds. As of November 2026, NOAA Fisheries also says that North Atlantic swordfish reach a maximum size of about 1,165 pounds and that the average size caught in the fishery is 50 to 200 pounds. Female swordfish are larger than male swordfish, and nearly all swordfish over 300 pounds, or 140 kilograms, are female. Because swordfish are difficult to age, the figure of about 9 years is best read as an approximation rather than a precise count for every fish.
What about the population as a whole? As of November 2026, according to NOAA Fisheries' 2022 stock assessment, North Atlantic swordfish is not overfished and not subject to overfishing. As of November 2026, the Florida Museum says that, with an international swordfish recovery plan from 1999, swordfish populations are on the road to recovery. Demand for swordfish in North America and Europe has put pressure on swordfish stocks, as of November 2026, and protective measures have been introduced to protect young swordfish. As of November 2026, FishBase lists the swordfish as Near Threatened on the IUCN Red List, assessed on 1 May 2021. These statements describe different places and different dates, so they cannot simply be added together.
Those statements describe a stock, a history of recovery and a worldwide list, and all of them can change, which is why each carries a date. The animal itself goes on with its days. Swordfish are often present in frontal zones, areas where ocean currents collide and productivity is high, and the ocean twilight zone is home to an abundance of fish and invertebrate life, so it is a rich place for swordfish to find food. A swordfish eats fish and squid, and scientists think it uses its sword when it hunts for food. Swordfish live in oceans around the world and hunt at many depths, from near the surface into deep water, staying deep in the day and rising near the surface at night, and they live mostly in midwater, at depths of about 200 to 600 meters, which is about 650 to 1,970 feet down.
Words to know
- overfished: too many caught
- spawning: egg-laying time
- stock: a fish group
