Swordfish

Swordfish, Xiphias gladius

Note:  This Species is currently considered to be ENDANGERED and if encountered should be handled accordingly.

Swordfish, Xiphias gladius. Fish caught in coastal waters off Puerto Los Cabos, Baja California Sur, July 2000. Length: 2.0 m (6 feet 6 inches). Photograph courtesy Eric Brictson, Gordo Banks Pangas, La Playita, Baja California Sur.

Swordfish, Xiphias gladius. Fish caught in coastal waters off San Diego, California, June 2021. Length: 2.05 m (6 feet 9 inches). Weight: 105 kg (231 lbs). Catch, photograph and identification courtesy of Dan and Hayden Fuller, San Diego, California.

The Swordfish, Xiphias gladius, is a member of the Swordfish or Xiphiidae Family, that is known in Mexico as pez espada. Globally, there are one species in the Xiphias Genus and one species in the Xiphidae Family, this species which is found in all Mexican waters of the Atlantic and the Pacific Oceans.

The Swordfish is a large fish that has an elongated cylindrical body that tapers to the rear. They are a blue-brown dorsally in color transitioning to silvery to light brown ventrally. Their first dorsal fin has a blackish-brown membrane. All other fins are brown or blackish-brown. Their head is large and is long and flat with a pointed bill which resembles a sword. Their mouth in adults lack teeth. Their first anal fin has 13 or 14 rays and is long and curved and located between the two dorsal fins; their second anal fin has 3 or 4 rays and is very small and found under the second dorsal fin; their caudal fin is large and strongly concave; their caudal peduncle has a strong keel; and, their first dorsal fin has 34 to 39 rays and is high and rigid with a short base ; the second dorsal fin has 4 to 6 rays and is small and set far back in the body; their pectoral fins have 16 to 18 rays and are set low on the sides; and, they do not have pelvic fins. The adults do not have scales. Fish over 1 m (3 feet 3 inches) do not have a lateral line.

The Swordfish is found as a solitary fish or in loose aggregations in all tropical and temperate waters of the Atlantic, Pacific and Indian Oceans from near the surface at night to depths up to 550 m (1,800 feet) during the day. They are normally an oceanic species that will visit coastal waters on occasion. They have been documented at a depth of 2,876 m (9,442 feet). They are known to lie on their sides and bask in the sun. They have been found in waters between 5oC (41oF) and 27oC (81oF) but the majority are found midwater above the thermal incline in waters between 18oC (64oF) and 22oC (72oF). They have the widest temperature tolerance of any billfish. They are known to breach which is believed to be a mechanism to remove pests such has remoras and lampreys. They reach a maximum of 4.55 m (14 feet 11 inches) in length and 650 kg (1,430 pounds) in weight with females growing faster and being larger. All fish over 140 kg (300 lbs) are females. As of January 1, 2023, the International Game Fish Association world record stood at 536 kg (1,182 lbs) with the fish caught in coastal waters off Chile, May 1953. They are sexually dimorphic with females being larger than males and those fish found in the Pacific are larger than those found in the Atlantic. They are ectothermic animals maintaining temperatures that are 10oC (18oF) to 15oC (27oF) above their surrounding water temperatures. They are highly migratory moving to the colder regions of their range to feed during warm water episodes. They are opportunistic nocturnal predators that utilize sword to kill their prey, and great speed being capable of reaching speeds of 36 km/h (22 mph), and agility to catch small fishes, including barracuda, hake, herring, mackerel, and rockfish. Juveniles consume pelagic crustaceans, fish, and squid. Adult fish have few natural predators but are preyed upon by Orca Whales and Shortfin Makos in small quantities; the juveniles are preyed upon by dorado, marlin, sailfish, a wide variety of sharks, and tuna. Solitary males and females pair up during spawning season. Batch spawning occurs in the upper water layer at depths up to 75 m (250 feet) in waters around 23oC (73oF). Each female lays between 1,000,000 and 29,000,000 buoyant eggs, that are fertilized externally, that are pelagic and hatch within 60 hours after fertilization. The females have life spans of sixteen years; the males twelve years.

The Swordfish is a resident of all Mexican waters of the Atlantic and Pacific Ocean.

The Swordfish can be distinguished from other billfishes by the shape of its elongated “bill” with its excessive length, flattened and oval cross section, the absence of teeth in the jaws, the lack of scales, and the lack of a lateral line.

From a conservation perspective the Swordfish is currently considered to be ENDANGERED. The Swordfish is heavily pursued by both commercial and recreational anglers on a global basis and subject to overfishing. They are famous for being strong powerful fighters. They are caught commercially at a level of 1,300,000 kg (2,900,000 pounds) from the North Atlantic waters and 100,000 tons globally primarily via long-lines with most of the fish taken in United States waters being sextually immature juveniles. In some regions long-line fishing has been recently banned in many coastal areas. They are considered to very dangerous during the landing process. They are an excellent food fish but are known to contain high levels of mercury. The Swordfish has been a focus on conservation programs including bans on sale and importations over the last thirty years. They were added to the Greenpeace International seafood red list in 2010.

A word of caution: these fish are ginormous wild animals and their spears are very dangerous!