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BILLFISH SPECIES
Just as eagles have done in the sky, billfish have dominated the seas as apex predators for years, and yet we know relatively little about them. Billfish include marlin, sailfish, swordfish and spearfish. Marlin, sailfish and spearfish are members of the family Istiophoridae, and swordfish are members of the family Xiphiidae. Billfish are best known for the elongated nasal bones that form their "bill". Like tunas, their bodies are also built for the endurance and speed needed to travel thousands of miles through the world's oceans in search of food.
Swordfish are commercially harvested for consumption, and even though marlin, sailfish and spearfish are not, they are caught incidentally by commercial fishermen and consumed in some countries. The harvesting differences have resulted in different governmental management plans for the Atlantic species.
Blue Marlin
Makaira nigricans (Atlantic) and M. mazara (Indian and Pacific)
Blue Marlin are found in all of the world's major oceans. They are one of the largest billfish species, and have been known to reach sizes of 1700 pounds (771 kg). Individuals over 350 pounds (159 kg) are most likely female. Atlantic blue marlin undergo rapid growth during the first year or two of their lives; however it typically takes 30 years for one to reach 1,000 pounds (454 kg). Blue marlin have the ability to make incredibly long journeys through the ocean. The record being a trip of 9,254 miles (14,893 km) from Delaware in the U.S. to the island of Mauritius off the southeast coast of Africa in the Indian Ocean.
Black Marlin
Makaira indica
Black marlin are found only in the Indian and Pacific Oceans. Like blue marlin, black marlin are known for making long distance migrations. One individual was recorded to have traveled 9,045 miles (14,556 km) across the Pacific Ocean from Australia to the Pacific coast of Costa Rica.
White Marlin
Tetrapturus albidus
White marlin are found in the Atlantic Ocean and in the Caribbean and Mediterranean Seas. They are among the smallest of the marlin, typically only reaching weights of 55 pounds (25 kg) and lengths of 5.5 feet (1.5 m). Individuals have been known to reach lengths of 7.5 feet (2.3 m) and weights of 180 pounds (82 kg). This species of marlin is the most frequently caught along the eastern coast of the U.S.
Striped Marlin
Tetrapturus audax
Striped Marlin are found throughout the Pacific and Indian Oceans and occassionaly on the Atlantic side of the Cape of Good Hope. These marlin are known for coming to the surface during strong winds and high waves, where they swim in the direction of the wind.
Sailfish
Istiophorus platypterus (Indo-Pacific) and I. albicans (Atlantic)
Sailfish are best known for their huge, sail-like dorsal fins. This fin can be up to twice the height of the body of the fish. They are the most commonly encountered of all the billfishes. Indo-Pacific sailfish are much larger than their Atlantic counterparts.
Spearfish
Tetrapturus pfluegeri (Atlantic longbill), T. angustirostris (Pacific shortbill) and T. belone (Mediterranean shortbill)
Though spearfish, the smallest of the billfishes, are found in all the world's oceans, they are rarely encountered in much of the world. They have the shortest bills of the billfish. Very little is known about these animals. It is believed that they have the shortest lifespan of the billfish, maturing at 2 years and living no more than 5 years.
Swordfish
Xiphias gladius
Swordfish are found in all of the world's oceans. They are easily identified by their flattened bills, shaped like the blade of a sword. They also differ from other billfish in that they have a single caudal keel, instead of two. They can reach sizes of 1200 pounds (540 kg). Similar to blue marlin, individuals that are over 300 pounds (136 kg) are most likely female. Swordfish have the ability to dive to 2,000 feet (610 m), although large individuals may be seen basking at the ocean's surface during the day.
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