Billfish
Encyclopedia
The term billfish is applied to a number of different large, predatory fish characterised by their large size (swordfish
can be over 4 metres long) and their long, sword-like bill. Billfish include the sailfish
and marlin
, which make up the family Istiophoridae, and the swordfish
, sole member of the family Xiphiidae. They are important apex predator
s feeding on a wide variety of smaller fish and cephalopod
s. While billfish are most common in tropical and subtropical waters, swordfish in particular are sometimes found in temperate waters as well. Billfish are characterized by a long spearlike or swordlike upper jaw or beak that may be used to stun prey during feeding; although this bill has been employed in apparent aggression to spear objects, including boats, it is not deliberately used to spear prey. These species are pelagic
, migratory, and found in all oceans.
and as game fish. Marlin and sailfish are eaten in many parts of the world, and important sport fisheries target these species, for example off the Atlantic coast of Florida
. Because of worries about declining populations, sport fishermen and conservationists now work together to gather information on billfish stocks and implement programs such as catch and release
, whereby fish are returned to the sea after they have been caught.
Swordfish are large and have meat that is firm and tasty, and are subject to intense fisheries pressure, and in many places where they were formerly abundant they are now comparatively rare.
Swordfish
Swordfish , also known as broadbill 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...
can be over 4 metres long) and their long, sword-like bill. Billfish include the sailfish
Sailfish
'Sailfish' are two species of fish in the genus Istiophorus, living in warmer sections of all the oceans of the world. They are predominately blue to gray in color and have a characteristic erectile dorsal fin known as a sail, which often stretches the entire length of the back...
and marlin
Marlin
Marlin, family Istiophoridae, are fish with an elongated body, a spear-like snout or bill, and a long rigid dorsal fin, which extends forward to form a crest. Its common name is thought to derive from its resemblance to a sailor's marlinspike...
, which make up the family Istiophoridae, and the swordfish
Swordfish
Swordfish , also known as broadbill 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...
, sole member of the family Xiphiidae. They are important apex predator
Apex predator
Apex predators are predators that have no predators of their own, residing at the top of their food chain. Zoologists define predation as the killing and consumption of another organism...
s feeding on a wide variety of smaller fish and cephalopod
Cephalopod
A cephalopod is any member of the molluscan class Cephalopoda . These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot...
s. While billfish are most common in tropical and subtropical waters, swordfish in particular are sometimes found in temperate waters as well. Billfish are characterized by a long spearlike or swordlike upper jaw or beak that may be used to stun prey during feeding; although this bill has been employed in apparent aggression to spear objects, including boats, it is not deliberately used to spear prey. These species are pelagic
Pelagic fish
Pelagic fish live near the surface or in the water column of coastal, ocean and lake waters, but not on the bottom of the sea or the lake. They can be contrasted with demersal fish, which do live on or near the bottom, and reef fish which are associated with coral reefs.The marine pelagic...
, migratory, and found in all oceans.
Exploitation and conservation
Billfish are exploited both as foodFishery
Generally, a fishery is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats,...
and as game fish. Marlin and sailfish are eaten in many parts of the world, and important sport fisheries target these species, for example off the Atlantic coast of Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
. Because of worries about declining populations, sport fishermen and conservationists now work together to gather information on billfish stocks and implement programs such as catch and release
Catch and release
Catch and release is a practice within recreational fishing intended as a technique of conservation. After capture, the fish are unhooked and returned to the water before experiencing serious exhaustion or injury...
, whereby fish are returned to the sea after they have been caught.
Swordfish are large and have meat that is firm and tasty, and are subject to intense fisheries pressure, and in many places where they were formerly abundant they are now comparatively rare.