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Atlantic sailfish

Istiophorus platypterus

What do they look like?

Large Indo-Pacific sailfish caught while trophy fishing have measured up to 340 cm, weighing as much as 100 kg. Their spindle-shaped body is long, flattened, and streamlined. Indo-Pacific sailfish have dark blue backs, with a mix of brown and light blue on their sides, and a silver-white color on their bellies. This species can be told apart from other similar species by their stripes of light blue dots along their sides. They have a long bill and file-like teeth. Their huge first dorsal fin is sail-like, with 42 to 49 rays, and a much smaller second dorsal fin, with 6 to 7 rays. Their pectoral fins are long, stiff, and hook-shape, with 18 to 20 rays. Their pelvic fins are along their chest and up to 10 cm long. Their scales become smaller as they age, most adult barely have any scales at all. Indo-Pacific sailfish are amazing swimmers that are able to swim in very quick bursts. To reduce drag and swim faster, these fish can also fold down their first dorsal fin. (Nakamura, 1985; Sagong, et al., 2013)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    50 to 100 kg
    110.13 to 220.26 lb
  • Average mass
    70 kg
    154.19 lb
  • Range length
    130 to 162 cm
    51.18 to 63.78 in
  • Average length
    140 cm
    55.12 in
  • Range basal metabolic rate
    250,000 to 1,500,000 cm3.O2/g/hr
  • Average basal metabolic rate
    525,000 cm3.O2/g/hr

Where do they live?

Indo-Pacific sailfish (Istiophorus platypterus) are found in temperate and tropical ocean waters. These fish are often found near tropical areas, especially near the equatorial regions of the Atlantic, Pacific, and Indian Oceans. They are found along Canada, the west coast of the United States, the western coast of South America, and some coastal areas of Africa. This species is mostly found along coastal areas, but they can also be found in more central ocean areas. (Nakamura, 1985; Prince, et al., 2006)

What kind of habitat do they need?

Indo-Pacific sailfish spend most of their time near the ocean surface, however, these fish sometimes dive into deeper waters where temperatures may reach as low as -8°C, although they prefer water temperatures between 25° to 30°C. Indo-Pacific sailfish migrate each year to higher latitudes during the summer and towards the equator in autumn. Larger adults tend to live in the easternmost areas of the Atlantic and Pacific oceans. (Hoolihan and Luo, 2007; Mourato, et al., 2010; Nakamura, 1985)

  • Range depth
    350 to 0 m
    1148.29 to 0.00 ft
  • Average depth
    10 m
    32.81 ft

How do they grow?

Indo-Pacific sailfish eggs are translucent and about 0.85 mm in diameter. The eggs contain a small amount of oil to nourish the embryo. The larval growth rate is influenced by the season, water conditions, and food availability. Newly-hatched larva are usually about 1.96 mm long, increasing to 2.8 mm after 3 days and up to 15.2 mm by 18 days. Juveniles grow very fast during their first year; females grow faster and are ready to breed sooner than males. After their first year, they grow much more slowly. Indo-Pacific sailfish reach adulthood when they are about 162 cm long or when they are about 3 to 4 years old. (Cerdenares-Ladron de Guevara, et al., 2011; Chiang, et al., 2006; Chiang, et al., 2004; Luthy, et al., 2005; Nakamura, 1985)

How do they reproduce?

Indo-Pacific sailfish breed year round in the layer of the ocean when the temperature begins to drop. Females extend their dorsal fin to attract mates. Males sometimes chase females to compete for the ability to spawn. (Nakamura, 1985)

During the spawning season in the western Pacific Ocean, Indo-Pacific sailfish migrate from the East China Sea and head south towards Australia for spawning. Indo-Pacific sailfish off the coast of Mexico head south to 28°C water. In the Indian Ocean, these fish are often found during the monsoon season when the waters reach ideal temperatures above 27°C. Indo-Pacific sailfish spawn throughout the year in tropical and subtropical regions, while their primary spawning season is during summer in higher latitudes. During this time, these fish can spawn multiple times. During mating, a male and female pair up and swim together and release both their eggs and sperm into the water. (Jolley, 1972; Luthy, et al., 2005; Nakamura, 1985)

  • How often does reproduction occur?
    Indo-Pacific sailfish breed three times a year.
  • Breeding season
    Indo-Pacific sailfish breed in the spring, summer, and fall.
  • Range number of offspring
    800,000 to 1,600,000
  • Average number of offspring
  • Range time to hatching
    60 to 70 hours
  • Range time to independence
    0 to 0 minutes
  • Range age at sexual or reproductive maturity (female)
    3 to 4 years
  • Range age at sexual or reproductive maturity (male)
    3 to 4 years

Indo-Pacific sailfish are broadcast spawners, which means the female releases eggs and the male releases sperm in the water to reproduce. Fish with this style of reproduction do not offer any parental care to their young. (Nakamura, 1985)

  • Parental Investment
  • no parental involvement

How long do they live?

Indo-Pacific sailfish may be able to survive up to 13 to 15 years. However, when these fish are caught and released, their average age is 4 to 5 years. (Prince, et al., 1986)

  • Range lifespan
    Status: wild
    4 to 5 years
  • Range lifespan
    Status: captivity
    unknown (low) years
  • Typical lifespan
    Status: wild
    13 to 15 years
  • Typical lifespan
    Status: captivity
    unknown (low) years

How do they behave?

Indo-Pacific sailfish spend most of their time in the upper 10 m of the water column and sometimes dive up to 350 m to find food. These animals eat whenever possible. They migrate and follow ocean currents with surface seawater temperatures above 28° C. Indo-Pacific sailfish travel over 3,600 km to spawn or find food. Juveniles swim in dense schools and adults swim in small groups, they also occasionally swim alone. These fish likely feed in groups according to their size. (Arizmendi-Rodriguez, et al., 2006; Mourato, et al., 2010; Nakamura, 1985)

  • Average territory size
    0 km^2

Home Range

This species does not maintain a home range or territory.

How do they communicate with each other?

While little is known about communication between individuals, sailfish can "flash" their body colors and other visual signals like dorsal fin movements during breeding. Their large eyes are flush to their head and are sensitive to low light. Indo-Pacific sailfish also have a pair of nares in front of their eyes, which they use to detect chemicals in the water. Like other bony fish, this species has a lateral line used to sense movement and pressure changes and structures in their ear canals that help them hear. (Nakamura, 1985)

What do they eat?

Indo-Pacific sailfish often eat fish such as mackerels, sardines, and anchovies, as well as cephalopods. While they follow prey, sailfish can be seen swimming quickly with their dorsal fins folded back halfway. When sailfish attack a school of fish, they fold their fin back completely so they can move even quicker. When they approach their prey, they turn their bill quickly and hit the prey, stunning or killing it. Indo-Pacific sailfish either hunt alone or in small groups. Aside from hunting schools of small fish, Indo-Pacific sailfish will also feed on fish found lower in the ocean, similar to other billfish such as blue marlin, swordfish, and striped marlin. The specific species they eat depends on the population sizes of their prey. (Arizmendi-Rodriguez, et al., 2006; Nakamura, 1985)

  • Animal Foods
  • fish
  • mollusks
  • aquatic crustaceans

What eats them and how do they avoid being eaten?

Indo-Pacific sailfish that are hooked by longlines have been attacked by great white sharks and killer whales. However, adult free-swimming sailfish are rarely attacked. (Nakamura, 1985)

What roles do they have in the ecosystem?

Indo-Pacific sailfish are top predators that affect the population of their prey. These fish may also host several parasites. (Nakamura, 1985; Speare, 1995)

Commensal or parasitic species (or larger taxonomic groups) that use this species as a host
  • Copepod Pannella instructa
  • Flatworm Callitetrarhynchus gracilis
  • Flatworm Floriceps minacanthus

Do they cause problems?

There are no known adverse effects of Indo-Pacific sailfish on humans.

How do they interact with us?

Indo-Pacific sailfish are frequently caught by the nets of commercial tuna fishers, they are also caught by gillnets, trolling, and harpooning. In 2011, an estimated 28,800 metric tons of Indo-Pacific sailfish were caught within the Indian Ocean. These fish are generally considered a prized sport fish, and their meat is often used for sashimi and sushi in Japan. (Nakamura, 1985)

  • Ways that people benefit from these animals:
  • food

Are they endangered?

Although they are not threatened or endangered, Indo-Pacific sailfish are considered a 'data-poor fishery' by the Indian Ocean Tuna Commission due to the increased fishing pressure, with an average yearly catch between 2008 to 2012 estimated at 26,283 metric tons. ("Status of the Indian Ocean Indo-Pacific sailfish (SFA: Istiophorus platypterus) resource", 2013)


Daniel Duong (author), San Diego Mesa College, Paul Detwiler (editor), San Diego Mesa College, Leila Siciliano Martina (editor), Animal Diversity Web Staff.


Indian Ocean Tuna Commission. Status of the Indian Ocean Indo-Pacific sailfish (SFA: Istiophorus platypterus) resource. IOTC-2013-SC16-R[E]. Seychelles: IOTC. 2013. Accessed May 24, 2014 at

Arizmendi-Rodriguez, D., L. Abitia-Cardenas, F. Galvan-Magana, I. Trejo-Escamilla. 2006. Food habits of sailfish Istiophorus platypterus off Mazatlan, Sinaloa, Mexico. Bulletin of Marine Science, 79/3: 777-791.

Cerdenares-Ladron de Guevara, G., E. Morales-Bojorquez, R. Rodriquez-Sanchez. 2011. Age and growth of the sailfish Istiophorus platypterus (Istiophoridae) in the Gulf of Tehuantepec, Mexico. Marine Biology Research, 7: 488-499.

Chiang, W., C. Sun, S. Yeh. 2004. Age and growth of sailfish (Istiophorus platypterus) in waters off eastern Taiwan. Fishery Bulletin, 102/2: 251-263. Accessed February 18, 2014 at

Chiang, W., C. Sun, S. Yeh, W. Su, D. Liu, W. Chen. 2006. Sex Ratios, Size at Sexual Maturity, and Spawning Seasonality of Sailfish Istiophorus platypterus from Eastern Taiwan. Bulletin of Marine Science, 79/3: 727-737.

Ehrhardt, N., M. Fitchett. 2006. On the Seasonal Dynamic Characteristics of the Sailfish, Istiophorus platypterus, in the Eastern Pacific off Central America. Bulletin of Marine Science, 79/3: 589-606. Accessed April 19, 2014 at

Hoolihan, J. 2005. Horizontal and vertical movements of sailfish (Istiophorus platypterus) in the Arabian Gulf, determined by ultrasonic and pop-up satellite tagging. Marine Biology, 146: 1015-1029.

Hoolihan, J., J. Luo. 2007. Determining summer residence status and vertical habitat use of sailfish (Istiophorus platypterus) in the Arabian Gulf. ICES Journal of Marine Science, 64: 1792-1799. Accessed February 18, 2014 at

Idrisi, N., T. Capo, S. Luthy, J. Serafy. 2003. Behavior, oxygen consumption and survival of stressed juvenile sailfish (Istiophorus platypterus) in captivity. Marine Freshwater Behaviour and Physiology, 36/1: 51-57.

Jolley, J. 1972. On the biology of Florida east coast Atlantic sailfish, (Istiophorus platypterus). Proceedings of the International Billfish Symposium, 675/2: 81-88. Accessed February 18, 2014 at

Luthy, S., J. Serafy, R. Cowen, K. Denit, S. Sponaugle. 2005. Age and growth of larval Atlantic sailfish, Istiophorus platypterus. Marine and Freshwater Research, 56: 1027-1035. Accessed February 18, 2014 at

Mourato, B., H. Hazin, P. Travassos, C. Arfelli, A. Amorim, F. Hazin. 2010. Environmental and spatial effects on the size and distribution of sailfish in the Atlantic Ocean. Ciencias Marinas, 36/3: 225-236.

Mourato, B., F. Carvalho, F. Hazin, J. Pachecco, H. Hazin, P. Travassos, A. Amorim. 2010. First Observations of Migratory Movements and Habitat Preference of Atlantic Sailfish, Istiophorus platypterus, in the Southwestern Atlantic Ocean. Collect. Vol. Sci. Pap. ICCAT, 65/5: 1740-1747. Accessed April 19, 2014 at

Nakamura, I. 1985. FAO Species Catalogue. Billfishes of the World, 5/125: 23-26. Accessed March 11, 2014 at

Post, J., J. Serafy, J. Ault, T. Capo, D. Sylva. 1997. Field and laboratory observations on larval Atlantic sailfish (Istiophorus platypterus) and swordfish (Xiphias gladius). Bulletin of Marine Science, 60/3: 1026-1034. Accessed February 18, 2014 at

Prince, E., D. Holts, D. Snodgrass, E. Orbesen, J. Luo, M. Domeier, J. Serafy. 2006. Transboundary Movement of Sailfish Istiophorus platypterus, off the pacific coast of Central America. Bulletin of Marine Science, 79/3: 827-838.

Prince, E., D. Lee, C. Wilson, J. Dean. 1986. Longevity and Age Validation of a Tag-recaptured Atlantic Sailfish Istiophorus platypterus, Using Dorsal Spines and Otoliths. Fishery Bulletin, 84/3: 493-502. Accessed April 02, 2014 at

Ravi, V., V. Sekar. 2010. Dietary composition of the sailfish Istiophorus platypterus (Shaw & Nodder, 1792) from Parangipettai, southeast coast of India. Journal of the Marine Biological Association of India, 52/1: 102-104. Accessed February 18, 2014 at

Sagong, W., W. Jeon, H. Choi. 2013. "Hydrodynamic characteristics of the sailfish (Istiophorus platypterus) and swordfish (Xiphias gladius) in gliding postures at their cruise speeds" (On-line pdf). Accessed February 18, 2014 at

Speare, P. 1995. Parasites as biological tags for sailfish Istiophorus platypterus from east coast Australian waters. Marine Ecology Progress Series, 118: 43-50. Accessed May 12, 2014 at

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Duong, D. 2014. "Istiophorus platypterus" (On-line), Animal Diversity Web. Accessed March 04, 2024 at

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