Broadbill swordfishSWO

Xiphias gladius
~120 cm LJFL

Characteristic features:

  • Bill very long and flattened, flat-oval in cross section
  • Eye large
  • A large, deep notch on both upper and lower caudal-fin origins
  • A single, large median keel on each side of caudal peduncle
  • Caudal fin large, forked and lunate
  • 2 separate dorsal and anal fins (except in juveniles < ~80–90 cm LJFL)
  • Scaleless (except in juveniles, that have scales until ~1 m in length)

Colour:

Upper surfaces blackish brown, lighter brown below. Fins brown to dark brown.

Size:

To 450 cm TL and up to 536 kg in weight1. Females are generally larger than males.

Important conditions and life stages:

juvenile
Xiphias gladius juvenile
~60 cm LJFL
    • First dorsal fin tall for much of its length
    • Scales present
    • No pelvic fins

Distribution:

Circumglobal in tropical, subtropical and sometimes cold waters.

View FAO distribution map.

Habitat:

Epi- and mesopelagic, oceanic, from the surface to at least 2,878 meters depth, found associated with drop-offs, offshore seamounts and submarine canyons. Swordfish tolerate a wide temperature range between 3–27°C, but prefer waters ranging between 18–22°C.

Biology:

This species is an opportunistic feeder, foraging predominantly on pelagic squid but also pelagic fishes. It uses the sword-like bill to stun or kill their prey. Swordfish undertake diurnal vertical migrations, generally moving to greater depths with lower temperatures during the day to forage, returning to warmer surface waters at night.2,3 Swordfish also undertake large horizontal migrations, moving between tropical and temperate waters to reach believed feeding and spawning grounds4,3. Swordfish are a fast growing species, with males maturing at a smaller size and younger age than females. In eastern Australia, length were 50% of individuals become mature is estimated at 221 and 101 cm LJFL corresponding to 9.9 and 0.9 years for females and males respectively.5 In the southwest Pacific age where 50% of female swordfish become mature is 4.34 years using ray-based estimations, and 4.42 years using otolith-based estimations.6 Off the coast of southeast Florida, it is estimated that male swordfish begin to mature at ~100 cm LJFL equating to 1 year, with all males recorded  mature by 150 cm LJFL, equating to 5 years. The smallest mature female was estimated at ~170 equating to 4 years, with all females becoming mature by 220 cm LJFL, equating to 9 years.7 In Eastern Australian waters, an extended spawning season occurs from September to May, peaking in December to February.8 Females display batch spawning and it is believed spawning occurs when water is <18°C. Maximum age estimates include 15 years9  18 years8 and 21 years in the southwest Pacific.6

Indonesian fisheries:

Caught by drift gill nets, longline, harpooning and by set nets.

Similar species:

Istiophoridae
Billfishes
Istiophoridae differ in having a bill that is round in cross section (vs. flat-oval); pelvic fins present (vs. absent); 2 keels on each side of caudal peduncle (vs. 1 median keel on either side); a narrow interdorsal space (vs. wide) and a shallow notch on both upper and lower origins of caudal fin (vs. deep notches).

Internal links:

Xiphias gladius market gallery

External links:

FishBase
The IUCN Red List of Threatened SpeciesTM

References

1.
IGFA. IGFA world record game fishes. International Game Fish Association Dania Beach, Florida. 2011;
2.
Takahashi M, Okamura H, Yokawa K, Okazaki M. Swimming behaviour and migration of a swordfish recorded by an archival tag. Marine and Freshwater Research. 2003;54(4):527–34.
3.
Abascal FJ, Mejuto J, Quintans M, Ramos-Cartelle A. Horizontal and vertical movements of swordfish in the Southeast Pacific. ICES Journal of Marine Science. 2009;67(3):466–74.
4.
Neilson JD, Smith S, Royer F, Paul SD, Porter JM, Lutcavage M. Investigations of horizontal movements of Atlantic swordfish using pop-up satellite archival tags. In: Tagging and tracking of marine animals with electronic devices. Springer; 2009. p. 145–59.
5.
Griggs LH, Francis M, Maolagáin C. Growth Rate, Age at Maturity, Longevity, and Natural Mortality Rate of Swordfish (Xiphias Gladius). Ministry of Fisheries; 2005.
6.
Farley J, Clear N, Kolody D, Krusic-Golub K, Eveson P, Young J. Determination of swordfish growth and maturity relevant to the southwest Pacific stock. WCPFC-SC12-2016/SA-WP-11; 2016.
7.
Taylor RG, Murphy MD. Reproductive biology of the swordfish Xiphias gladius in the Straits of Florida and adjacent waters. Fishery Bulletin. 1992;90(4):809–16.
8.
Young JW, Drake AD. Age and growth of broadbill swordfish (Xiphias gladius) from Australian waters. CSIRO Marine Research; 2004.
9.
DeMartini EE, Uchiyama JH, Humphreys Jr RL, Sampaga JD, Williams HA. Age and growth of swordfish (Xiphias gladius) caught by the Hawaii-based pelagic longline fishery. Fishery Bulletin. 2007;105(3):356–67.