All About Sailfish: The Ocean’s Speedster

Leave a comment / / Updated on: 20th October 2023

Scientific nameIstiophorus WeightUp to 90–100 kilograms (198–220 pounds)
PronunciationSeil-fishLengthUp to 3 meters (9.8 feet)
ClassificationActinopterygii, Istiophoriformes, IstiophoridaeLocationAtlantic, Indian, and Pacific Oceans

The Sailfish

The Sailfish | GeorgePeters via iStock

Known for its incredible speed, fascinating hunting techniques, notable dorsal fin, and captivating nature, the sailfish reigns in the shallow waters of the Atlantic and Indo-Pacific Oceans. 

They’re also famous for their unique coloration and color-changing abilities!

These creatures have been around for almost 60 million years and are still arousing the interest of thousands of scientists and even more wildlife enthusiasts!

They are excellent predators that have evolved to hunt in groups and rely on their sharp bills and tall dorsal fins to trap and catch prey.

Are you curious enough already? Keep reading, as we’ve gathered quite a comprehensive list of incredible facts about sailfish!

Gage Beasley's In-Demand Plush Toys
Gage Beasley’s In-Demand Plush Toys

Taxonomy and Classification

Gage Beasley's Sailfish Plush Toy
Gage Beasley’s Sailfish Plush Toy

Sailfish form the Istiophorus genus, which consists of two species:

  • Istiophorus albicans, the Atlantic sailfish
  • Istiophorus platypterus, the Indo-Pacific sailfish

It’s worth mentioning that not all taxonomists recognize both species, as no particular mtDNA differences have been found between the two. 

Nonetheless, FishBase (a global fish species database) confirms the validity of both.

The genus is part of the Istiophoridae family of marlins, which makes sailfish closely related to species like the black marlin or the longbill spearfish. 

Together, they are classified under the Istiophoriformes order of bony fish and the Actinopterygii class of ray-finned fish.

Physical Characteristics

The unique long bill structure of the Sailfish’s jaw | ByronD via iStock

Sailfish are mostly known for their upper jaw, which is modified into a long bill, and for the tall, sail-like first dorsal fin, which runs along most of the body length. 

This dorsal fin consists of roughly 42–49 rays. The second dorsal fin and the anal fins are similar in shape and size. The pelvic fins are quite long, almost reaching the first anal fin.

It is believed that sailfish can change colors when they’re excited or in danger, which is why outlining a precise coloration is quite challenging. 

However, the standard color pattern is likely the following: they’re dark blue on the upper parts, brownish-blue on the sides, and whitish on the undersides. 

The ventral parts are covered in brown spots, and each side of the body is covered in approximately 20 light blue bars made of dots. 

All the fins are blackish blue except the anal fin, which is white. Additionally, the first dorsal fin is decorated with black spots.

Compared to other members of their family, sailfish are quite small, reaching only 1.7–3.4 meters (5.6–11.2 feet) long. 

Some Atlantic populations are even smaller, measuring only 1.2 meters (3.9 feet) long. They weigh up to 100 kilograms (220 pounds). Females are slightly larger than males.

Habitat and Distribution

Map of the world’s oceans | Fayethequeen via iStock

Sailfish are found in the tropical and temperate waters of the Atlantic Ocean, the Indian Ocean, and the Pacific Ocean. 

Occasionally, they are spotted in the Mediterranean Sea, reaching the habitat through the Suez Canal during a migratory route.

These fish are known to prefer shallow waters close to coasts, islands, and reefs. Some populations depend on coral reefs for breeding and feeding. 

If necessary, they can go up to 200 meters (656 feet) beneath the water surface. Sailfish remain in waters with temperatures between 21 and 28 degrees Celsius (69.8 and 82.4 degrees Fahrenheit).

Behavior and Social Structure

Sailfish rodeo | Luis Beristain via iStock

Sailfish typically engage in seasonal migrations.

These migrations are likely affected by wind conditions, water temperature, food availability, and spawning purposes. 

Some have been observed covering more than 3,600 kilometers (2,237 miles) to find the perfect spawning grounds. 

Otherwise, they spend most of their time in shallow waters, occasionally diving deeper to forage. 

Juvenile sailfish are typically spotted swimming during the day in schools organized by their size, whereas adults travel in small groups. 

Nonetheless, some sailfish individuals seem to be more solitary.

Furthermore, sailfish are renowned as one of the world’s fastest fish species! Some sources even mention that it’s the fastest marine animal. 

However, scientists haven’t fully confirmed the exact maximum swimming speed these creatures can reach.

A sailfish (Istiophorus) eats a fish from a fast moving bait ball in the waters off Isla Mujeres, Mexico
A sailfish (Istiophorus) eats a fish from a fast moving bait ball in the waters off Isla Mujeres, Mexico / NaluPhoto via Istock

Some tops rank them second-fastest after black marlins. Supposedly, black marlins recorded a maximum speed of 132 km/h (82 mph), whereas sailfish reached 109.19 km/h (67.8 mph). 

Nonetheless, the maximum speed of black marlins is now widely disputed, as is that of sailfish. 

Apparently, the record of 109.19 km/h (67.8 mph) was attained in a series of tests performed at Long Key, Florida, when sailfish leaped 91 meters (299 feet) in three seconds. 

Specialists translated this to the speed we mentioned above.

Therefore, this is only a leaping speed, not a swimming speed. A sailfish’s swimming speed, on the other hand, is probably only 35–55 km/h (21.7–34.2 mph). 

As such, are they really the fastest fish? Hopefully, future studies will either confirm or disapprove of this statement!

Let’s not forget about the iconic sailfish acrobatics! One reason why they’re the subject of fascination for so many fishermen and wildlife enthusiasts is that they can perform amazing jumps out of the water!

Diet and Feeding

Gonna catch them all | NaluPhoto via iStock

Sailfish are carnivorous and typically go for the following prey:

  • Tuna
  • Mackerel
  • Herring
  • Needlefish
  • Halfbeak
  • Sardines
  • Anchovy
  • Jumbo squid
  • Triggerfish
  • Paper nautilus
  • Crabs
  • Gastropods
  • Sea robins
  • Octopus
  • Zooplankton (when sailfish are young)
Gonna hunt alone because I am speed! | Marco_Zucchini via iStock

If they hunt alone, sailfish will rely on their speed and long bills to stun and kill prey. 

When they hunt in groups, sailfish surround their prey and rely on their tall dorsal fins to create a barrier so that prey cannot escape.

These creative predators were seen pursuing fish schools at half speed, with their fins half-folded back. 

Then, when they considered a moment favorable, they folded their fins back completely, swam after prey at full speed, made a sharp turn while fully expanding the fins, confronted the fish, and then hit them with their bills. The prey was eaten head first.

Nonetheless, although sailfish have quite a well-developed hunting technique, statistics show that only 24% of attacks are successful.

Research also shows that sailfish use side-to-side movements to slash prey, and it is believed that each individual has a preference regarding what side it prefers for hitting prey. 

Specialists believe that the fish that are regular prey for sailfish may learn their predators’ hunting preferences and, therefore, be more successful in avoiding predation.

Reproduction and Life Cycle

Sailfish larvae | Alexandre Wagner Silva Hilsdorf via Research Gate Public Domain

The beginning of the spawning period depends on each sailfish population’s geographic location. 

For example, the spawning season for those living in the northwestern Atlantic waters starts in April and lasts until July-August. 

The peak spawning season of the sailfish living in the Pacific is during the summer months, although other sources mention that the Indo-Pacific sailfish can breed year-round in tropical and subtropical regions.

Before fertilization, females extend their dorsal fins above the water surface. This behavior attracts males.

Since they reproduce via external fertilization, male and female sailfish release the sperm and eggs, respectively, into the water. Females may release as many as 4 million eggs!

Sailfish eggs have a diameter of roughly 0.85 millimeters (0.03 inches). 

The larvae are 1.96 millimeters (0.07 inches) long upon hatching and reach almost 3 millimeters (0.11 inches) within a few days. 

At this stage, they do not have the long, pointed bill known in adults. Only when the offspring are 6 millimeters (0.23 inches) long do they start the jaw transformation.

When they’re 18 days old, sailfish measure 15.2 millimeters (0.6 inches) long. 

Afterward, they lose all their larval characteristics and start growing quite fast until one year of age, upon which the growth rate decreases but never stops.

At 1.6 meters (5.2 feet) long, sailfish are considered mature. Sexual maturity is attained at 3–4 years of age. Sailfish have a life expectancy of 10–15 years.

Ecological Role and Interactions

The sailfish / Giorgio Cavallaro via Istock

Sailfish are a predatory species, and, therefore, their presence has a major impact on their ecosystems, as they help control the prey populations and maintain a healthy and balanced habitat. 

Apart from this, sailfish serve as hosts for 34 parasitic species, including protozoans, flukes, tapeworms, roundworms, white suckerfish, and marlin sucker.

Nevertheless, they’re not the only ones with the same function! Although it is believed sailfish aren’t as affected by food competition as other billfish, some populations overlap in geographical range with white and blue marlins, which can lead to some rivalry.

Although adult sailfish are rarely killed by other predators, attacks from great white sharks and killer whales are not uncommon. 

Even seabirds were spotted attacking sailfish. If they stumble upon a juvenile, they may even kill it!

Conservation Status and Threats

Atlantic white marlin big game sport fishing over blue Atlantic ocean | LUNAMARINA via iStock

The IUCN Red List recognizes only one sailfish species, Istiophorus platypterus, which was assessed as Vulnerable in 2021. 

Upon thorough research, scientists concluded that the global sailfish population suffered a 30% reduction over the past 12 years.

Although sailfish aren’t as valuable commercially as other fish because their meat is too tough to be eaten, they’re sought after as game fish by recreational fishermen and are caught as bycatch.

Sailfish populations are primarily threatened by coastal recreational and artisanal fleets, trawl and gillnet fisheries, and tuna longline fisheries. 

Can you imagine that Indian billfish catches increased from 5,000 metric tons (5,511 short tons) to 29,000 metric tons (31,967 short tons) over a decade? 

This increase is attributed to the development of the Sri Lankan longline fishery. From 2011 until 2017, billfish catches increased to 33,280 metric tons (36,685 short tons).

Besides the threats mentioned above, sailfish populations are negatively affected by climate change and water pollution.

Unique Adaptations and Survival Strategies

The long bill of a sailfish | LUNAMARINA via iStock

Besides their distinctive long bill used to catch and kill prey and their tall dorsal fin that plays an important role in trapping prey, sailfish have an interesting communication system, which helps them interact with each other.

While the other two characteristics help them stay alive by ensuring they have enough food, the communication system promotes the continuation of their species. 

More precisely, it is believed that, during the breeding season, individuals rely on changing their body colors to find and attract mates, which ensures successful fertilization.

Their color-changing abilities may also help in alerting other members of the group of imminent danger, as some sources mention that sailfish change their colors when threatened as well. However, this hasn’t been fully confirmed and requires further research.

Sailfish have a lateral line, which they rely on to feel any pressure changes in the water. 

Additionally, the pair of nares in front of their eyes are sensitive enough to detect any chemicals in the surrounding water.

And how can we forget about how fast they swim? No wonder they have few to no predators within their habitats and can feed on anything they set their eyes on!

Furthermore, the fact that they’ve learned to hunt in groups and developed quite captivating hunting techniques is a major advantage in ensuring their survival and keeping their populations steady.

Last but not least, their ability to thrive in both shallow and deeper waters is an excellent adaptation that helps them survive in their habitats.

Cultural Significance and Human Interactions

Local Seychellois man finding and transporting a Indo-Pacific Sailfish found it on the beach | Wirestock via iStock

Literature lovers may have first heard of a sailfish when they saw the iconic portrait of the famous author Ernest Hemingway posing with a sailfish he had caught!

Sailfish have long been regarded as symbols of strength, wisdom, courage, good luck, and resilience. 

Although not as popular in arts and culture as other marine creatures, sailfish are renowned among fishing and wildlife enthusiasts for their grace, agility, speed, and excellent hunting techniques.

These marine creatures are typically friendly toward humans. However, if they feel threatened or if they’re approached while guarding their eggs, sailfish can become quite aggressive and attack the intruders. 

Considering how sharp their bills are, attacks usually cause serious injuries.

For example, in 2022, a 70-year-old woman was stabbed by a sailfish while her boat companions were trying to reel it in on a fishing line. 

The sailfish attacked the boat so quickly that she had no time to react. The woman was taken to the hospital for urgent care.

As such, swimmers and divers are strongly advised to educate themselves on sailfish distribution and ecosystem preferences and to avoid intruding on their territories. 

Anglers are advised to prepare themselves properly if they’re planning to catch sailfish, as the process can be quite tricky.

Future Prospects and Research

Sailfish on the loose | Wirestock via iStock

Due to their uniqueness, beauty, interesting adaptations, captivating behavior and lifestyle, and distinctive migratory routes, sailfish are extensively studied.

They’ve aroused the curiosity of thousands of scientists who are researching various aspects of their biology. 

Many studies focus on the use of their bills, the structure of their brains, the dietary preferences linked to geographic locations, and the hunting behavior of solitary sailfish.

As with any other oceanic creatures, many things are yet unknown, and we, wildlife enthusiasts, are eager to learn what other awe-striking details specialists will discover in the near future!


What a journey we’ve had going through all these captivating details about sailfish! In the end, sailfish have undoubtedly earned the status of being iconic symbols of the oceans.

Besides their unmatched speed, unique appearance, and creative hunting techniques, sailfish play an important ecological role by maintaining their ecosystems healthy and balanced.

Although their meat isn’t sought after, sailfish are a popular game fish in recreational fishing. 

Besides this, they’re often caught as bycatch. As a consequence, their population numbers are decreasing, and conservation efforts are a must to avoid the extinction of these oceanic speedsters.

We can spread awareness, contribute to conservation efforts, and make sure not to intrude on their territories to avoid injuring ourselves and causing too much stress to their population.


Are swordfish and sailfish the same?

Swordfish and sailfish are not the same fish. Swordfish are scientifically called Xiphias gladius and are part of the Xiphiidae family, whereas sailfish are part of the Istiophoridae family.

Is it safe to eat sailfish?

Sailfish is safe to eat. Nonetheless, their meat is quite tough, and people rarely catch these fish for consumption.

Do sailfish have teeth?

Sailfish have file-like teeth.

Which is faster – a swordfish or a sailfish?

Some sources list the swordfish after the sailfish in terms of maximum recorded speed.


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