There are millions of types de peces in the sea and many ways of swimming for each one. There are those who do not know how to swim well, others who they swim in a peculiar way and others whose speed is incredible. Today we're going to talk about a fish whose swimming ability is truly spectacular. It's about the sailfishWith its unique, enormous dorsal fin, this fish can swim at tremendous speed in pursuit of its prey or to escape predators.
If you want to know everything about this fish, keep reading
Sailfish characteristics
The sailfish, with a scientific name Istiophorus albicans, was described as a species native to the Atlantic Ocean. It is also popularly known as marlin fish by some fishermen, although it's not a marlin Strictly speaking, marlins belong to the genus Tetrapturus/Makaira, while the sailfish is part of the genus Istiophorus within the family Istiophoridae.
There is another recognized species that lives in the Indian and Pacific Oceans, Istiophorus platypterus. Both present bluish or gray tones silvery white on the back and belly. Generally speaking, the Atlantic species tends to be smaller, although sizes vary depending on the region and food availability.
Another peculiarity of this fish it's his snoutIt has a narrow shape that ends in a very sharp point, rounded in cross-section, similar to a saber. In action, it is impressive how it can swim at great speeds in pursuit of its prey. Its hydrodynamic morphology and powerful caudal peduncle allow it to cut through the water with extraordinary ease.
The first dorsal fin is the most distinctive feature: it is tall, with a very long base and sail-shaped, and usually has between 42 and 49 radii (although ranges between 37 and 49 have been cited). The second dorsal fin is smaller, with 6–8 rays. The tail, large and strongly forked, is attached via a powerful caudal peduncle provided with two lateral keels that help stabilize at high speeds.
In the paired fins, the pectoral fins are long and pointed, with 18–20 rays, and the pelvic fins are very long, foldable in a groove and able to reach almost the anus. It has two anal fins (the first with 12–17 rays and the second with 6–7). The body is covered by small triangular scales, and on its flanks it often displays approximately 20 vertical bars made up of multiple light blue spots. The large dorsal "sail" can be deployed to increase the profile during hunting or folded down to reduce drag.
As for size, you can find sailfish specimens weighing 100 kilograms in weight, and the most common is that they are around 50 kg, with lengths that can exceed 3 meters if the total length with the beak is considered.
At short distances, the metallic blue sailfish is considered by many specialists to be the fastest fish in the seaVarious studies have estimated peak speeds of around 110–119 km/h (approximately 30 m/s), figures that help explain why their prey have little room to maneuver. This ability is achieved thanks to a slender, muscular body, a rigid C-shaped tail, and a tall dorsal fin that, when folded, reduces drag and, when unfolded, facilitates control in turns and maneuvers.
It is often confused with the marlin or swordfishAlthough it shares a family with marlins, the swordfish belongs to the monospecific family Xiphiidae. The sailfish is easily distinguished by its enormous, sail-shaped dorsal fin, which is much taller than its body is deep.
Habitat
This fish lives the upper waters of the oceansIt doesn't usually live at great depths and prefers warm and temperate waters. In its range, it has great ease in finding its prey, and thanks to its speed, its task of catching food isn't too arduous.
The Atlantic sailfish varies its distribution area depending on the water temperature and, in some cases, conditions such as wind direction and strength. At the extremes of its distribution (both north and south) it appears more frequently during the warmer months, as it prefers waters with moderate temperatures. These movements are also related to the migration of their prey, which he follows to ensure food.
It is typically found above the thermocline in warm surface waters. When migrating, it may approach coastal areas to take advantage of current corridors and areas of high productivity. Its ideal temperature is usually between 21 and 29 ºCOn occasion, fry have been found in the Mediterranean Sea after straying during their migratory journeys.
In the Indian-Pacific region, it is found in temperate and tropical waters throughout the world. Its distribution is tropical and equatorial, extending from coastal regions of temperate latitudes to central oceans. It is an epipelagic species: it spends most of its adult life in the upper layer, near or above the thermocline, where light and currents favor the location of prey.
Meals
This fish is completely carnivorous and is among the most skilled predators in the oceansIt is undoubtedly one of the fastest in temperate and warm waters. Its diet includes squid, octopus, flying fish, juvenile tuna, and other schooling pelagic fish such as sardines and mackerel, which it pursues in the surface water column.
It can use its beak to separate individuals from the school with precise lateral strikes, which makes them more vulnerable to capture. They often ram, wound, or stun their prey with their snout before swallowing it. They are capable of diving to depths of about 30 meters, although they prefer to hunt near the surface where sunlight gives them a visual advantage.
Sailfish usually stay near the reef edges or slopes to gain a broader view of their surroundings and corner prey. When food is abundant, they may hunt individually; however, there are situations in which several individuals coordinate an attack by deploying their dorsal fins to increase the visible surface area and "compress" the school against a wall of water.
They compete for food with dolphins and sharks, but their combination of speed and maneuverability makes them highly effective. At short distances, sailfish accelerate incredibly fast: traveling 50 meters in a couple of seconds is well within their capabilities, leaving their prey with little time to react.
Behavior
Sailfish are primarily a species (hence their ability to migrate in search of prey). Large schools are rarely observed, although they sometimes form small groups when the hunting strategy requires it, especially in dense schools. de peces.
It is a species that tests the waters before launching into the hunt to avoid interference. It can alternate bursts of high speed with phases of controlled gliding, folding its dorsal fin during fast movements and unfolding it when it needs to slow down, turn, or appear larger to compact the school.
Males and females exhibit very similar hunting behavior: they surround their prey and force it to close ranks. The attacks are swift and accurate, and are usually preceded by a dorsal fin deployment This broadens the hunter's profile, increasing its intimidating power. Momentary color changes (highlighting the lateral bars) have also been described during the chase, possibly related to communication or dynamic camouflage.
In addition to its accelerations, the sailfish performs spectacular jumps out of the water. These leaps, which are also observed in marlins and swordfish, can be part of hunting behavior, escape, or even an attempt to free themselves from parasites and hooks.
Reproduction
Sailfish reproduction has some peculiarities. The female spawns several times throughout the year, releasing their eggs in the open sea, generally where the water temperature is warm, around 26°C. These areas are usually located near coasts or on platforms with good circulation and productivity.
For each laying, the female drifts on the surface. Once the eggs are laid, the male fertilizes them externally. Due to the exposure of the eggs and larvae to predators and changing conditions, only a small percentage survive to advanced stages.
The hatched fry, initially tiny, float near the surface, so early mortality is very high. However, the fry develop rapidly: when they reach about five centimeters in length, their fins are fully functional, improving their chances of survival.
The most frequent spawning seasons are concentrated between , depending on the region. As adults, sailfish's most common natural enemies are large sharks and other pelagic predators that share their habitat.
Conservation, speed and responsible sport fishing
Because of its power and beauty, the sailfish is considered one of the most prized trophies for sport fishing. It is generally caught by trolling on the high seas, using artificial lures, live or dead bait, and even imitation squid. It is known for its great resilience: after being hooked, it alternates between underwater runs and jumping to try to free itself from the hook.
This popularity has put pressure on some populations when best practices aren't followed. The practice has spread to multiple destinations, allowing people to enjoy fishing while minimizing the impact on the species. Recommendations include using circle hooks (which reduce damage), keeping the fish in the water during release, avoiding prolonged handling, and using equipment appropriate for its size to shorten the fight and prevent extreme exhaustion.
Another warning sign mentioned by biologists and fishermen in different regions is the reduction in average size of some captured individuals, an indicator that fishing pressure may be affecting the age structure. Therefore, monitoring programs, closed seasons when appropriate, and education for the recreational sector are key to ensuring healthy populations over time.
Regarding speed, records of peaks close to . Although these figures usually correspond to specific estimates under very specific conditions, they illustrate the sailfish's extraordinary hydrodynamic adaptation: a caudal peduncle with lateral keels that provide stability, a rigid crescent-shaped tail for power transfer, a folding dorsal fin to reduce drag, and a long snout that helps it slice through the water.
It is often confused with marlins or swordfish due to its jumps and its "beak", but the sailfish is immediately recognizable for its large, sail-shaped dorsal fin, the presence of two anal fins, and the pattern of lateral blue bars. Correctly identifying each species is important for fisheries management and conservation.
With this information, you'll be able to learn more about one of the most incredible fish in the sea. From its unmistakable anatomy and surprising speed to its hunting and reproductive habits and the challenges it faces, the sailfish embodies the elegance and power of the ocean. Watching it in action, whether in the wild or in pictures, helps us appreciate the need for protect their populations through responsible practices and admiring him for what he is: a supreme athlete of the sea.
