Temporal range: Late Cretaceous–present
|The largest billfish, the Atlantic blue marlin weighs up to 820 kg (1800 lb) and has been classified as a vulnerable species.|
Betancur-R et al., 2013
|Cladistically included but traditionally excluded taxa|
The term billfish refers to a group of predatory fish characterised by prominent bills, or rostra, and by their large size; some are longer than 4 m (13 ft). Billfish include sailfish and marlin, which make up the family Istiophoridae, and swordfish, sole member of the family Xiphiidae. They are apex predators which feed on a wide variety of smaller fish, crustaceans, and cephalopods. These two families are sometimes classified as belonging to the order Istiophoriformes, a group with origins in the Late Cretaceous around 71 million years ago with the two families diverging from one and another in the Late Miocene around 15 million years ago. However, they are also classified as being closely related to the mackerels and tuna within the suborder Scombroidei of the order Perciformes. However, the 5th edition of the Fishes of the World does recognise the Istiophoriformes as a valid order, albeit including the Sphyraenidae, the barracudas.
Billfish are pelagic and highly migratory. They are found in all oceans, although they usually inhabit tropical and subtropical waters; swordfish are found in temperate waters, as well. Billfish use their long spears or sword-like upper beaks to slash at and stun prey during feeding. Their bills can also be used to spear prey, and have been known to spear boats (probably accidentally), but they are not normally used in that way. They are highly valued as gamefish by sports fishermen.
The term billfish refers to the fishes of the families Xiphiidae and Istiophoridae. These large fishes are "characterized by the prolongation of the upper jaw, much beyond the lower jaw into a long rostrum which is flat and sword-like (swordfish) or rounded and spear-like (sailfishes, spearfishes, and marlins)."
The 12 species of true billfish are divided into two families and five genera. One family, Xiphiidae, contains only one species, the swordfish Xiphias gladius, and the other family, Istiophoridae, contains 11 species in four genera, including marlin, spearfish, and sailfish. Controversy exists about whether the Indo-Pacific blue marlin, Makaira mazara, is the same species as the Atlantic blue marlin, M. nigricans. FishBase follows Nakamura (1985) in recognizing M. mazara as a distinct species, "chiefly because of differences in the pattern of the lateral line system".
|Family||Genus||Common name||Scientific name||Maximum
|Xiphiidae||Xiphias||Swordfish||Xiphias gladius (Linnaeus, 1758)||455 cm||300 cm||650 kg||years||4.49||||||Least concern|
|Atlantic sailfish||Istiophorus albicans (Latreille, 1804)||315 cm||cm||58.1 kg||17 years||4.50||||Not assessed|
|Indo-Pacific sailfish||Istiophorus platypterus (Shaw, 1792)||340 cm||cm||100 kg||years||4.50||||||Least concern|
|Istiompax||Black marlin||Istiompax indica (Cuvier, 1832)||465 cm||380 cm||750 kg||years||4.50||||Data deficient|
|Makaira||Indo-Pacific blue marlin||Makaira mazara (Jordan and Snyder, 1901)||500 cm||350 cm||625 kg||4.5 – 6 years||4.46||||Vulnerable |
|Atlantic blue marlin||Makaira nigricans (Lacépède, 1802)||500 cm||290 cm||820 kg||years||4.50||||Vulnerable|
|Tetrapturus||White marlin||Tetrapturus albidus/Kajikia albida Poey, 1860||300 cm||210 cm||82.5 kg||years||4.48||||Vulnerable|
|Shortbill spearfish||Tetrapturus angustirostris Tanaka, 1915||200 cm||cm||52 kg||years||4.50||||Data deficient|
|Striped marlin||Tetrapturus audax/Kajikia audax (Philippi, 1887)||350 cm||cm||200 kg||years||4.58||||||Near threatened|
|Roundscale spearfish||Tetrapturus georgii Lowe, 1841||184 cm||cm||24 kg||years||4.37||||Data deficient|
|Mediterranean spearfish||Tetrapturus belone Rafinesque, 1810||240 cm||200 cm||70 kg||years||4.50||||Least concern|
|Longbill spearfish||Tetrapturus pfluegeri Robins and de Sylva, 1963||254 cm||165 cm||58 kg||years||4.28||||Least concern|
A number of other fishes have pronounced bills or beaks, and are sometimes referred to as billfish, despite not being true billfish. Halfbeaks look somewhat like miniature billfish, and the sawfish and sawshark, which are cartilaginous fishes with long, serrated rostrums. Needlefish are sometimes confused with billfish, but they are "easily distinguished from the true billfish by having both jaws prolonged, the dorsal and anal fins both single and similar in size and shape, and the pelvic fins inserted far behind the pectorals." Paddlefish have elongated rostrums containing electroreceptors that can detect weak electrical fields. Paddlefish are filter feeders and may use their rostrum to detect zooplankton.
Billfish have a long, bony, spear-shaped bill, sometimes called a snout, beak or rostrum. The swordfish has the longest bill, about one-third its body length. Like a true sword, it is smooth, flat, pointed and sharp. The bills of other billfish are shorter and rounder, more like spears.
Billfish normally use their bills to slash at schooling fish. They swim through the fish school at high speed, slashing left and right, and then circle back to eat the fish they stunned. Adult swordfish have no teeth, and other billfish have only small file-like teeth. They swallow their catch whole, head-first. Billfish don't normally spear with their bills, though occasionally a marlin will flip a fish into the air and bayonet it. Given the speed and power of these fish, when they do spear things the results can be dramatic. Predators of billfish, such as great white and mako sharks, have been found with billfish spears embedded in them. Pelagic fish generally are fascinated by floating objects, and congregate about them. Billfish can accidentally impale boats and other floating objects when they pursue the small fish that aggregate around them. Care is needed when attempting to land a hooked billfish. Many fisherman have been injured, some seriously, by a billfish thrashing its bill about.
|Striped Marlin Bait Ball YouTube|
Billfish are large swift predators which spend most of their time in the epipelagic zone of the open ocean. They feed voraciously on smaller pelagic fish, crustaceans and small squid. Some billfish species also hunt demersal fish on the seafloor, while others descend periodically to mesopelagic depths. They may come closer to the coast when they spawn in the summer. Their eggs and larvae are pelagic, that is they float freely in the water column. Many grow over three metres (10 feet) long, and the blue marlin can grow to five metres (16 feet). Females are usually larger than males.
Like scombroids (tuna, bonito and mackerel), billfish have both the ability to migrate over long distances, efficiently cruising at slow speeds, and the ability to generate rapid bursts of speed. These speed bursts can be quite astonishing, and the Indo-Pacific sailfish has been recorded making a burst of 68 miles per hour (110 km/h), nearly top speed for a cheetah and the highest speed ever recorded for a fish.
Some billfish also descend to considerable mesopelagic depths. They have sophisticated swim bladders which allow them to rapidly compensate for pressure changes as the depth changes. This means that when they are swimming deep, they can return swiftly to the surface without problems. "Like the large tuna, some billfish maintain their body temperature several degrees above ambient water temperatures; this elevated body temperature increases the efficiency of the swimming muscles, especially during excursions into the cold water below the thermocline."
In 1936 the British zoologist James Gray posed a conundrum which has come to be known as Gray's paradox. The problem he posed was how dolphins can swim and accelerate so fast when it seemed their muscles lacked the needed power. If this is a problem with dolphins it is an even greater problem with billfish such as swordfish, which swim and accelerate faster than dolphins. In 2009, Taiwanese researchers from the National Chung Hsing University introduced new concepts of "kidnapped airfoils and circulating horsepower" to explain the swimming capabilities of swordfish. The researchers claim this analysis also "solves the perplexity of dolphin's Gray paradox". They also assert that swordfish "use sensitive rostrum/lateral-line sensors to detect upcoming/ambient water pressure and attain the best attack angle to capture the body lift power aided by the forward-biased dorsal fin to compensate for most of the water resistance power."
Billfish have prominent dorsal fins. Like tuna, mackerel and other scombroids, billfish streamline themselves by retracting their dorsal fins into a groove in their body when they swim. The shape, size, position and colour of the dorsal fin varies with the type of billfish, and can be a simple way to identify a billfish species. For example, the white marlin has a dorsal fin with a curved front edge and is covered with black spots. The huge dorsal fin, or sail of the sailfish is kept retracted most of the time. Sailfish raise them if they want to herd a school of small fish, and also after periods of high activity, presumably to cool down.
Billfish occur worldwide in temperate and tropical waters. They are highly migratory oceanic fish, spending much of their time in the epipelagic zone of international water following major ocean currents. Migrations are linked to seasonal patterns of sea surface temperatures. They are sometimes referred to as "rare event species" because the areas they roam over in the open seas are so large that researchers have difficulty locating them. Little is known about their movements and life histories, so assessing how they can be sustainably managed is not easy.
Unlike coastal fish, billfish usually avoid inshore waters unless there is a deep dropoff close to the land. Instead, they swim along the edge of the continental shelf where cold nutrient rich upwellings can fuel large schools of forage fish. Billfish can be found here, cruising and feeding "above the craggy bottom like hawks soaring along a ridge line".
Billfish are among the most coveted of big gamefish, and major recreational fisheries cater to the demand. In North America, "the apex of the salt water pursuits is billfishing, the quest for elusive blue marlin and sailfish in the deep blue water about 60 miles out." A lot of resources are committed to the activity, particularly in the construction of private and charter billfishing boats to participate in the billfishing tournament circuit. These are expensive purpose-built offshore vessels with powerfully driven deep sea hulls. They are often built to luxury standards and equipped with many technologies to ease the life of the deep sea recreational fisherman, including outriggers, flying bridges and fighting chairs, and state of the art fishfinders and navigation electronics.
The boats cruise along the edge of the continental shelf where billfish can be found down to 200 metres (600 ft), sometimes near weed lines at the surface and submarine canyons and ridges deeper down. Commercial fishermen usually use drift nets or longlines to catch billfish, but recreational fishermen usually drift with bait fish or troll a bait or lure. Billfish are caught deeper down the water column by drifting with live bait fish such as ballyhoo, striped mullet or bonito. Alternatively, they can be caught by trolling at the surface with dead bait or trolling lures designed to imitate bait fish.
Most recreational fishermen now tag and release billfish. A 2003 study surveyed 317,000 billfish known to have been tagged and released since 1954. Of these, 4122 were recovered. The study concluded that, while tag and release programs have limitations, they provided important information about billfish that cannot currently be obtained by other methods.
Billfish make good eating fish, and are high in omega-3 oils. Blue marlin has a particularly high oil content. However, because billfish have high trophic levels, near the top of the food web, they also contain significant levels of mercury and other toxins. According to the United States Food and Drug Administration, swordfish is one of four fishes, along with tilefish, shark, and king mackerel, that children and pregnant women should avoid due to high levels of methylmercury found in these fish and the consequent risk of mercury poisoning. 
|Nutritional value per 100 g (3.5 oz)|
|Energy||144 kJ (34 kcal)|
|Vitamin A||120 IU|
|†Percentages are roughly approximated using US recommendations for adults. |
Source: USDA Nutrient Database
|Comparative mercury levels|
|Tilefish||1.450||Gulf of Mexico|
|King mackerel||0.182||South Atlantic|
|Flatfish *||0.056||Flounder, plaice and sole|
|* indicates methylmercury only was analyzed (all other results are for total mercury)|
Billfish are primarily marketed in Japan, where they are eaten raw as sashimi. They are marketed fresh, frozen, canned, cooked and smoked. It is not usually a good idea to fry billfish. Swordfish and marlin are best grilled or broiled, or eaten raw as in sashimi. Sailfish and spearfish are somewhat tough and are better cooked over charcoal or smoked.
Billfish are exploited both as food and as fish. Marlin and sailfish are eaten in many parts of the world, and many sport fisheries target these species. Swordfish are subject to particularly intense fisheries pressures, and although their survival is not threatened worldwide, they are now comparatively rare in many places where once they were abundant. The istiophorid billfishes (marlin and spearfish) also suffer from intense fishing pressures. High mortality levels occur when they are caught incidentally by longline fisheries targeting other fish. Overfishing continues to "push these declines further in some species". Because of these concerns about declining populations, sport fishermen and conservationists now work together to gather information on billfish stocks and implement programs such as catch and release, where fish are returned to the sea after they have been caught. However, the process of catching them can leave them too traumatised to recover. Studies have shown that circle fishing hooks do much less damage to billfish than the traditional J-hooks, yet they are at just as effective for catching billfish. This is good for conservation, since it improves survival rates after release.
The stocks for individual species in billfish longline fisheries can "boom and bust" in linked and compensatory ways. For example, the Atlantic catch of blue marlin declined in the 1960s. This was accompanied by an increase in sailfish catch. The sailfish catch then declined from the end of the 1970s to the end of the 1980s, compensated by an increase in swordfish catch. As a result, overall billfish catches remained fairly stable.
"Many of the world's fisheries operate in a data poor environment that precludes predictions about how different management actions will affect individual species and the ecosystem as a whole." In recently years pop-up satellite archival tags have been used to monitor billfish. The capability of these tags to recover useful data is improving, and their use should result in more accurate stock assessments. In 2011, a group of researchers claimed they have, for the first time, standardized all available data about scombrids and billfishes so it is in a form suitable for assessing threats to these species. The synthesis shows that those species which combine a long life with a high economic value, such as the Atlantic blue marlin and the white marlin, are generally threatened. The combination puts such species in "double jeopardy".
The Atlantic blue marlin (Makaira nigricans) is a species of marlin endemic to the Atlantic Ocean. It is closely related to, and usually considered conspecific with, the Indo-Pacific blue marlin, then simply called blue marlin. Some authorities still consider both species distinct.
The Atlantic blue marlin (hereafter, blue marlin) feeds on a wide variety of organisms near the surface. It uses its bill to stun, injure, or kill while knifing through a school of fish or other prey, then returns to eat the injured or stunned fish. Marlin is a popular game fish. The relatively high fat content of its meat makes it commercially valuable in certain markets. It is the national fish of the Commonwealth of the Bahamas and is featured on its coat of arms.
Blue marlin are distributed throughout the tropical and subtropical waters of the Atlantic Ocean. A bluewater fish that spends the majority of its life in the open sea far from land, the blue marlin preys on a wide variety of marine organisms, mostly near the surface, often using its bill to stun or injure its prey.
Females can grow up to four times the weight of males. The maximum published weight is 818 kg (1,803 lb) and length 5 m (16.4 ft).Adult blue marlin have few predators apart from killer whales, sharks, and humans. They are sought after as a highly prized game fish by anglers and are taken by commercial fishermen, both as a directed catch and as bycatch in major industrial tuna fisheries. Blue marlin are currently considered a threatened species by the IUCN due to overfishing , particularly in the international waters off the coast of Portugal where they migrate to breed in the June/July months.Some other historic English names for the blue marlin are Cuban black marlin, ocean gar, and ocean guard.Big-game fishing
Big-game fishing, also known as offshore sportfishing, offshore gamefishing, or blue-water fishing is a form of recreational fishing, targeting large fish such as tuna and marlin which game fisherman regard as having "sporting qualities".Circle hook
A circle hook is a type of fish hook which is sharply curved back in a circular shape. It has become widely used among anglers in recent years because the hook generally catches more fish and is rarely swallowed. Since the circle hook catches the fish on the lips at the corner of its mouth, it usually decreases the mortality rates of released fish as compared to J-hook (like O'Shaughnessy or Octopus hooks) which are often swallowed by the fish, causing damage to the gills or vital organs.
The circle hook's shape allows it to only hook onto an exposed surface, which in the case of a fish means the corner of its mouth. The fish takes the baited hook and swallows it, and as the hook is reeled in, it is safely pulled out of the fish until it reaches the mouth. At this point it will catch the corner of the mouth, resulting in fewer gut-hooked fish.
It is important to not strike (or set the hook) when the fish bites, but rather just reel in. The act of striking while using a circle hook often results in the hook being pulled out of the fish altogether.
Studies have shown that circle hooks do less damage to billfish than the traditional J-hooks, yet they are at just as effective for catching billfish. This is good for conservation, since it improves survival rates after release.Dorsal fin
A dorsal fin is a fin located on the back of most marine and freshwater vertebrates such as fishes, cetaceans (whales, dolphins, and porpoises), and the (extinct) ichthyosaur. Most species have only one dorsal fin, but some have two or three.
Wildlife biologists often use the distinctive nicks and wear patterns which develop on the dorsal fins of large cetaceans to identify individuals in the field.
The bony or cartilaginous bones that support the base of the dorsal fin in fish are called pterygiophores.Fishing industry in Palau
The fishing industry in Palau is of prime importance to the national economy and a major source of livelihoods. As of 2007, there were three major fishing companies operating in the islands.
Fishing in the country is by no means without issues; the industry is subject to problems with migrating fish and hurricanes.
The locals are adept at casting, trolling, fly fishing, bottom-fishing, bone fishing and spear fishing, as well as teaching angling to tourists. Among the fish caught are barracuda, tuna, tarpon, trevally, marlin, wahoo, sailfish, grouper, billfish and snapper.Hemiramphus
Hemiramphus is a genus of schooling marine fish commonly called halfbeaks, garfish, or ballyhoos, and are members of the family Hemiramphidae. They inhabit the surface of warm temperate and tropical sea, and feed on algae, plankton, and smaller fish. Hemiramphus species are edible but are more important as food fish for larger predatory species including dolphinfish and billfish.Istiophoriformes
Istiophoriformes is an order of bony fish which is not recognised by some authorities while others include the two extant billfish families, Xiphiidae and Istiophoridae, and others include the barracudas, the family Sphyraenidae.Marlin fishing
Marlin fishing (also called billfishing) is considered by some game fishermen to be a pinnacle of offshore game fishing, due to the size and power of the four marlin species and their relative rareness. Fishing for marlin captured the imagination of some sport fishermen in the 1930s, when well-known angler/authors Zane Grey, who fished for black, striped, and blue marlin in the Pacific, and Ernest Hemingway, who fished the Florida Keys, Bahamas and Cuba for Atlantic blue marlin and white marlin, wrote extensively about their pursuit and enthused about the sporting qualities of their quarry.
These days a lot of resources are committed to the construction of private and charter billfishing boats to participate in the billfishing tournament circuit. These are expensive purpose-built offshore vessels with powerfully driven deep sea hulls. They are often built to luxury standards and equipped with many technologies to ease the life of the deep sea recreational fisherman, including outriggers, flying bridges and fighting chairs, and state of the art fishfinders and navigation electronics.Marlin are part of the billfish family, of which 10 species are of the most interest to anglers: Atlantic and Pacific blue marlin, black marlin, white marlin, striped marlin, Atlantic sailfish, Pacific sailfish, longbill spearfish, shortbill spearfish, and swordfish.Percomorpha
The Percomorpha is a large clade of bony fish that includes the tuna, seahorses, gobies, cichlids, flatfish, wrasse, perches, anglerfish, and pufferfish.Peter Miller (angler)
Peter Miller is a professional angler and three-time sailfish tournament world champion. Miller is the host of Bass 2 Billfish on the NBC Sports Network, which is in its 6th season. Miller has filmed Bass 2 Billfish in collaboration with the Make-A-Wish Foundation, including a two-part episode that premiered in January-February 2015. Other notable episodes of Bass 2 Billfish include a two-part episode filmed with the Florida Army National Guard, which premiered in February, 2015. Miller was chosen by Florida Governor Rick Scott to be part of the "Sportsman for Scott" Coalition which supports the rights of hunters and fishers in Florida.Rostrum (anatomy)
In anatomy, the term rostrum (from the Latin rostrum meaning beak) is used for a number of phylogenetically unrelated structures in different groups of animals.Sailfish
A sailfish is a fish of the genus Istiophorus of billfish living in colder areas of all the seas of the earth. They are predominantly blue to gray in colour and have a characteristic erectile dorsal fin known as a sail, which often stretches the entire length of the back. Another notable characteristic is the elongated bill, resembling that of the swordfish and other marlins. They are, therefore, described as billfish in sport-fishing circles.Scombroidei
Scombroidei is a suborder of the Perciformes, the largest order of fish. The suborder includes the barracuda, tuna, and mackerel, as well as the billfish.Swordfish
Swordfish (Xiphias gladius), also known as broadbills in some countries, are large, highly migratory, predatory fish characterized by a long, flat bill. They are a popular sport fish of the billfish category, though elusive. Swordfish are elongated, round-bodied, and lose all teeth and scales by adulthood. These fish are found widely in tropical and temperate parts of the Atlantic, Pacific, and Indian Oceans, and can typically be found from near the surface to a depth of 550 m (1,800 ft). They commonly reach 3 m (9.8 ft) in length, and the maximum reported is 4.55 m (14.9 ft) in length and 650 kg (1,430 lb) in weight.They are the sole member of their family, Xiphiidae.Tag and release
Tag and release is a form of catch and release fishing in which the angler attaches a tag to the fish, records data such as date, time, place, and type of fish on a standardized postcard, and submits this card to a fisheries agency or conservation organization. Anglers who catch tagged fish report their location, date, and time, as well as the tag number to established points of contact. South Carolina has had such a program since 1974.
A tag and release program is in place in NSW, Australia.USS Billfish
Two ships of the United States Navy have borne the name Billfish, after the billfish.
USS Billfish (SS-286), was a Balao-class submarine, commissioned in 1943 and struck in 1968.
USS Billfish (SSN-676), was a Sturgeon-class submarine, commissioned in 1971 and struck in 1999.USS Billfish (SS-286)
USS Billfish (SS-286), a Balao-class submarine, was the first ship of the United States Navy to bear the generic name for any fish, such as gar or spearfish, with bill-shaped jaws. Her keel was laid at Portsmouth Navy Yard on 23 July 1942. She was launched on 12 November 1942 sponsored by Mrs. Lewis Parks (wife of Lieutenant Commander Lew Parks), and commissioned on 20 April 1943 with Lieutenant Commander Frederic C. Lucas, Jr., in command.
Between 12 August 1943 and 27 August 1945 Billfish made eight war patrols out of Pearl Harbor. During these patrols she sank three freighters totaling 4,074 tons and five smaller craft. Part of her seventh and eighth patrols were spent on plane guard duty off Japan.
On 11 November 1943, in the Makassar Strait, a Japanese destroyer severely damaged Billfish with a depth charge attack, driving her to a depth of 650 feet (200 m), some 250 feet (76 m) below her test depth while continuing the attack. Many of the crew were badly injured; Lieutenant Charles W. Rush found himself the senior man still able to carry out his duties. He assumed command and began attempting to escape the attack. Realizing that his boat's damaged fuel tanks were leaking profusely and the enemy was undoubtedly tracking him by the oil slick he was leaving, he reversed course so precisely that he was able to proceed back down his previous track, using the floating oil slick as cover instead of a trail.
Meanwhile, Chief Electrician's Mate John D. Rendernick took action from his battle station and led emergency repairs, which included using a hydraulic jack to reposition the port main motor, which had been knocked off its foundation, and filling a leaking stern torpedo tube with grease.
After 12 hours, the attack ceased. Four hours after that, under the cover of night, Rush surfaced the boat, recharged batteries using the single operating generator, completed repairs, and continued her patrol.
For his actions, Rush earned the Navy Cross. Rendernick was awarded the Navy Silver Star, posthumously, and on 17 August 2004 the Naval Submarine Training Center (NAVSUBTRACEN) John D. Rendernick Damage Control Wet Trainer at Pearl Harbor was named in his honor.
Billfish arrived at Pearl Harbor from her last war patrol on 27 August 1945, and was ordered to the Atlantic. She arrived at New Orleans, Louisiana, on 19 September and spent the next nine months in maneuvers and training. Following inactivation at Portsmouth Navy Yard (June - October 1946) she was towed to New London, Connecticut, by ATR-64 and went out of commission in reserve there 1 November 1946.
Billfish received seven battle stars for her World War II service.
The Billfish, like several other World War II boats, did not end her service at the end of the war. From 1 January 1960 until 1 April 1968 she served as a training vessel for the Naval Reserve, First Naval District, at the South Boston Annex of the Boston Naval Shipyard. She was stricken from the list of Navy ships on 1 April 1968 and subsequently sold for scrapping in 1971.USS Billfish (SSN-676)
USS Billfish (SSN-676), a Sturgeon-class attack submarine, was the second ship of the United States Navy to be named for the billfish, a name used for any fish, such as gar or spearfish, with bill-shaped jaws.White marlin
White marlin (Kajikia albida), also known as Atlantic white marlin, marlin, skilligalee, is a species of billfish that lives in the epipelagic zone of the tropical and subtropical Atlantic Ocean. They are found between the latitudes of 45° N and 45° S in waters deeper than 100 m. Even though white marlin are found in bodies of water that are deeper than 100 m they tend to stay near the surface. White marlin have been found near banks, shoals, and canyons, but they are not limited to those locations. They prefer warm surface temperatures greater than 22 °C.