Pacific crevalle jack
Encyclopedia
The Pacific crevalle jack, Caranx caninus, is a species
of large marine
fish
classified in the jack family Carangidae
. The Pacific crevalle jack is distributed through the tropical waters of the eastern Pacific Ocean
from California
in the north to Peru
in the south, including several offshore islands. The species is best identified by its deep body and mostly unscaled breast, as well as other more detailed anatomical features. The species is known to grow to a maximum length of 101 cm and a weight of 19.7 kg
. There has been significant disagreement on the status of the species in the scientific literature, with many claiming it to be conspecific with or subspecific
to the Atlantic Caranx hippos (crevalle jack
). The most recent review of the crevalle jacks strongly concluded it to be a separate species based on the development of hyperostosis
and fin colouring. It is predominantly a schooling
inshore species, inhabiting sandy and rocky substrates, although larger individuals are occasionally found living pelagically to depths of 350 m. The Pacific crevalle jack is a fast swimming predator, taking a variety of fish, crustacean
s and other small invertebrate
s. Spawning
is thought to occur year-round, although peaks occur during November and May. The Pacific crevalle jack is an important species to commercial fisheries, with data available from Colima
in Mexico
indicating it accounts for up to 15% of the entire yearly catch. Pacific crevalle jack are highly rated gamefish, taken by both bait and a variety of lures, but are considered relatively poor quality
food.
Caranx
, one of a number of groups known as the jacks or trevallies. Caranx itself is part of the larger jack and horse mackerel family Carangidae
, a group of percoid
fishes in the order Perciformes
. The species is part of what William Smith-Vaniz and Kent Carpenter term the Caranx hippos species complex, a group of three closely related and anatomically similar species, which also includes Caranx hippos (Crevalle jack
) and Caranx fischeri (Longfin crevalle jack
).
The species was first properly scientifically described by the British zoologist Albert Günther
in 1867 based on a specimen taken from Panama
, which was designated to be the holotype
. He named the species Caranx caninus, with the specific epithet meaning 'dog like'. Apart from disagreements pertaining to the possible conspecificity of the species with Caranx hippos, the taxonomy has been very stable, with not one independent redescription and naming. There has, however, been considerable debate in the past as to whether the Pacific crevalle jack is the same species as its Atlantic counterpart, Caranx hippos. To this end it has previously been referred to as C. hippos, and John Nichols
argued it was a subspecies, creating the trinomial name Caranx hippos caninus. Yoshio Hiyama also referred the species to a subgenus
he created; Tricropterus, creating the name Caranx (Tricropterus) hippos, which is now considered invalid. The most recent review of the species by Smith-Vaniz and Carpenter treated the fish as a separate species, citing differences in the development of hyperostosis
and differing anal fin colours as evidence of different species. The species is commonly
referred to as the 'Pacific crevalle jack' or 'Pacific jack crevalle' due to its close appearance to the Atlantic 'crevalle jack', as well as a variety of Spanish names.
in weight. It is similar to most other jacks of the genus Caranx, having a moderately deep and compressed oblong
body, with the dorsal profile more convex than the ventral profile, particularly anteriorly. The dorsal fin
is in two distinct sections; the first consisting of 8 spine and the second of 1 spine and 19 to 21 soft rays. The anal fin consists of 2 anteriorly detached spines followed by 1 spine and 16 to 17 soft rays. The pectoral fins are falcate, and consist of 19 to 21 soft rays, while the caudal fin is strongly forked. The species lateral line
is moderately arched anteriorly, with 58 to 79 scales in this section, while the straight section contains 0 to 7 scales
and 34 to 43 strong scute
s. The breast is devoid of scales with the exception of a small patch of scales in front of the pelvic fins. The species has well-developed adipose eyelids, while its dentition consists of an outer row of widely spaced canine
teeth and an inner band of villiform teeth in the upper jaw
, with a row of widely spaced conical teeth on the lower jaw. The Pacific crevalle jack has 21 to 27 gill raker
s and 24 vertebrae. There are significant differences in the development of hyperostosis
between this species and C. hippos.
The Pacific crevalle jack is a bluish green to bluish black dorsally, fading to a silvery white or golden shade ventrally. Juveniles are generally lighter in colour, also possessing five dark vertical
bars on their sides. The fins are all white dusky with the exception of the anal fin and lower caudal fin lobe, which are white to brownish orange, with the ventral surface of the caudal peduncle also this colour. This contrasts to the bright lemon yellow anal and lower caudal fins of C. hippos. The Pacific crevalle jack also has a black spot on the base of its pectoral fins, as well as a dark blotch on the margin of the operculum
.
The Pacific crevalle jack inhabits the tropical to subtropical waters of the eastern Pacific Ocean
. The species ranges along the western America
n coastline from Lobos de Tierra Island, Peru
in the south and north to San Diego Bay
, California
. The species is generally rare north of the Gulf of California
, however El Nino events which bring warm tropical waters further north than usual transport Pacific crevalle jack and other species beyond their normal range. All occurrences of the species in San Diego Bay have been attributed El Nino events in that year. The species is also known from several offshore
Pacific islands including the Galapogos
, Malpelo
, Cocos
, and Revillagigedo Islands
.
The Pacific crevalle jack is most common in coastal regions, although is occasionally found in more pelagic settings, with the species not known to live deeper than 350 m. In coastal waters the species prefers sandy and rocky substrates, including protected bay
s, lagoon
s and harbours, where large schools of the species form. Larger individuals are often solitary, and living in deeper offshore
environments. Pacific crevalle jack are also common in estuaries, usually as juveniles which preferentially inhabit these environments, but also as adults that make their way into brackish waters and tidal streams. Juveniles are known to penetrate well upstream, indicating a wide salinity
tolerance.
The Pacific crevalle jack is a schooling
fish for much of its life, forming moderate to large aggregations that can move quite rapidly. Older fish tend to be more solitary, moving offshore to greater depths. It is one of the most abundant pelagic species throughout its range, making it both ecologically
and economically important. The species is a strong, fast swimming predator that takes predominantly small fish, as well as crustacean
s such as prawn
s and various other benthic invertebrates, although no detailed data on diet has been collected.
Individuals begin reaching sexual maturity
at 67 cm in males and 65 cm in females, with reproduction thought to occur year round. There are peaks in spawning
activity however, with these peaks reported as January–February and August in Colombia
and May and November in Mexico
. The egg
s are pelagic, as are the newly hatched larva
e.
Several studies on yearly growth in the species have given slightly different results, although the maximum difference between these studies is 5 cm per year. After the first year, the species is 19.02 to 20.64 cm long, after the second it is 29.86 to 32.95 cm, and its is 36.8 to 42.44 cm long after the third year. According to the von Bertalanffy growth equation
s that govern the species growth, the species may live as long as 12 or 15 years, or even 37 years as calculated in one study. These growth equations are generated using the fish's otolith
s, which add annual growth rings. These also show yearly periods of slow and fast growth, with August to February having the fastest growth due to the rainy season providing increased runoff and nutrient
s to the coast. Slowest growth occurs during March to August, although one of the main spawning peaks occurs during this period.
of the species are not kept, making it impossible to estimate total annual catches. Where these statistics are kept, however, it is apparent that it is one of the most important species in its range, with the species accounting for up to 15% of the total annual catch in Colima, Mexico
. This translates as around 76 tonnes on average, just for the state of Colima. The species is taken year round by a variety of methods including trawling, fence and fixed nets, as well as hook and line methods. It is sold at market either fresh, frozen, smoked, salted
or dried, and is also utilized as a source of fishmeal and oil. Despite the large numbers taken, the Pacific crevalle jack is considered a second or third class commercial product, fetching fairly low prices at market
. The value of the fish does change throughout its range based on local opinion of the fish.
The Pacific crevalle jack is also a major target for anglers
throughout its range, and can be taken by live bait as well as various lure types including surface poppers and fast retrieved metal slugs and spoons. It is generally viewed as marginal table fair
, although bleeding the fish immediately after capture is said to improve the flavor.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of large marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...
fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
classified in the jack family Carangidae
Carangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...
. The Pacific crevalle jack is distributed through the tropical waters of the eastern Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
from California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
in the north to Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....
in the south, including several offshore islands. The species is best identified by its deep body and mostly unscaled breast, as well as other more detailed anatomical features. The species is known to grow to a maximum length of 101 cm and a weight of 19.7 kg
Kilogram
The kilogram or kilogramme , also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram , which is almost exactly equal to the mass of one liter of water...
. There has been significant disagreement on the status of the species in the scientific literature, with many claiming it to be conspecific with or subspecific
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
to the Atlantic Caranx hippos (crevalle jack
Crevalle jack
The crevalle jack, Caranx hippos is a common species of large marine fish classified within the jack family, Carangidae...
). The most recent review of the crevalle jacks strongly concluded it to be a separate species based on the development of hyperostosis
Hyperostosis
Hyperostosis is an excessive growth of bone. It may lead to exostosis. It occurs in many musculoskeletal disorders.-See also:* Infantile cortical hyperostosis* SAPHO syndrome* Hyperostosis frontalis interna...
and fin colouring. It is predominantly a schooling
Shoaling and schooling
In biology, any group of fish that stay together for social reasons are said to be shoaling , and if, in addition, the group is swimming in the same direction in a coordinated manner, they are said to be schooling . In common usage, the terms are sometimes used rather loosely...
inshore species, inhabiting sandy and rocky substrates, although larger individuals are occasionally found living pelagically to depths of 350 m. The Pacific crevalle jack is a fast swimming predator, taking a variety of fish, crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s and other small invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s. Spawning
Spawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
is thought to occur year-round, although peaks occur during November and May. The Pacific crevalle jack is an important species to commercial fisheries, with data available from Colima
Colima
Colima is one of the 31 states which, with the Federal District, make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima....
in Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
indicating it accounts for up to 15% of the entire yearly catch. Pacific crevalle jack are highly rated gamefish, taken by both bait and a variety of lures, but are considered relatively poor quality
Fish (food)
Fish is a food consumed by many species, including humans. The word "fish" refers to both the animal and to the food prepared from it. Fish has been an important source of protein for humans throughout recorded history.-Terminology:...
food.
Taxonomy and naming
The Pacific crevalle jack is classified within the genusGenus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Caranx
Caranx
Caranx is a genus of tropical to subtropical marine fish in the jack family Carangidae, commonly known as jacks, trevallies and kingfishes. They are moderate to large sized, deep bodied fishes which are distinguished from other carangid genera by specific gill raker, fin ray and dentition...
, one of a number of groups known as the jacks or trevallies. Caranx itself is part of the larger jack and horse mackerel family Carangidae
Carangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...
, a group of percoid
Percoidei
Percoidei is one of eighteen suborders of bony fish in the order Perciformes. Many commercially harvested fish species are contained in this suborder, including the snappers, jacks, whitings, groupers, bass, perches and porgies.-Divisions:...
fishes in the order Perciformes
Perciformes
The Perciformes, also called the Percomorphi or Acanthopteri, is one of the largest orders of vertebrates, containing about 40% of all bony fish. Perciformes means perch-like. They belong to the class of ray-finned fish and comprise over 7,000 species found in almost all aquatic environments...
. The species is part of what William Smith-Vaniz and Kent Carpenter term the Caranx hippos species complex, a group of three closely related and anatomically similar species, which also includes Caranx hippos (Crevalle jack
Crevalle jack
The crevalle jack, Caranx hippos is a common species of large marine fish classified within the jack family, Carangidae...
) and Caranx fischeri (Longfin crevalle jack
Longfin crevalle jack
The longfin crevalle jack, Caranx fischeri, is a recently described species of large marine fish classified in the jack family, Carangidae. It inhabits the subtropical waters of the east Atlantic Ocean, ranging along the African coast from Mauritania south at least to Moçamedes in southern Angola,...
).
The species was first properly scientifically described by the British zoologist Albert Günther
Albert C. L. G. Günther
Albert Karl Ludwig Gotthilf Günther FRS, also Albert Charles Lewis Gotthilf Günther , was a German-born British zoologist, ichthyologist, and herpetologist....
in 1867 based on a specimen taken from Panama
Panama
Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...
, which was designated to be the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
. He named the species Caranx caninus, with the specific epithet meaning 'dog like'. Apart from disagreements pertaining to the possible conspecificity of the species with Caranx hippos, the taxonomy has been very stable, with not one independent redescription and naming. There has, however, been considerable debate in the past as to whether the Pacific crevalle jack is the same species as its Atlantic counterpart, Caranx hippos. To this end it has previously been referred to as C. hippos, and John Nichols
John Treadwell Nichols
John Treadwell Nichols was an American ichthyologist.-Biography:Nichols was born as son of John White Treadwell Nichols in Jamaica Plain, Boston, Massachusetts. In 1906 he studied vertebrate zoology at Harvard College where he graduated to Bachelor of Arts...
argued it was a subspecies, creating the trinomial name Caranx hippos caninus. Yoshio Hiyama also referred the species to a subgenus
Subgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...
he created; Tricropterus, creating the name Caranx (Tricropterus) hippos, which is now considered invalid. The most recent review of the species by Smith-Vaniz and Carpenter treated the fish as a separate species, citing differences in the development of hyperostosis
Hyperostosis
Hyperostosis is an excessive growth of bone. It may lead to exostosis. It occurs in many musculoskeletal disorders.-See also:* Infantile cortical hyperostosis* SAPHO syndrome* Hyperostosis frontalis interna...
and differing anal fin colours as evidence of different species. The species is commonly
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
referred to as the 'Pacific crevalle jack' or 'Pacific jack crevalle' due to its close appearance to the Atlantic 'crevalle jack', as well as a variety of Spanish names.
Description
The Pacific crevalle jack is a relatively large fish, growing to a maximum recorded size of 101.6 cm in length and 19.7 kgKilogram
The kilogram or kilogramme , also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram , which is almost exactly equal to the mass of one liter of water...
in weight. It is similar to most other jacks of the genus Caranx, having a moderately deep and compressed oblong
Rectangle
In Euclidean plane geometry, a rectangle is any quadrilateral with four right angles. The term "oblong" is occasionally used to refer to a non-square rectangle...
body, with the dorsal profile more convex than the ventral profile, particularly anteriorly. The dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
is in two distinct sections; the first consisting of 8 spine and the second of 1 spine and 19 to 21 soft rays. The anal fin consists of 2 anteriorly detached spines followed by 1 spine and 16 to 17 soft rays. The pectoral fins are falcate, and consist of 19 to 21 soft rays, while the caudal fin is strongly forked. The species lateral line
Lateral line
The lateral line is a sense organ in aquatic organisms , used to detect movement and vibration in the surrounding water. Lateral lines are usually visible as faint lines running lengthwise down each side, from the vicinity of the gill covers to the base of the tail...
is moderately arched anteriorly, with 58 to 79 scales in this section, while the straight section contains 0 to 7 scales
Scale (zoology)
In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran species, scales are plates on the surface of the insect wing, and provide coloration...
and 34 to 43 strong scute
Scute
A scute or scutum is a bony external plate or scale, as on the shell of a turtle, the skin of crocodilians, the feet of some birds or the anterior portion of the mesonotum in insects.-Properties:...
s. The breast is devoid of scales with the exception of a small patch of scales in front of the pelvic fins. The species has well-developed adipose eyelids, while its dentition consists of an outer row of widely spaced canine
Canine tooth
In mammalian oral anatomy, the canine teeth, also called cuspids, dogteeth, fangs, or eye teeth, are relatively long, pointed teeth...
teeth and an inner band of villiform teeth in the upper jaw
Jaw
The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of...
, with a row of widely spaced conical teeth on the lower jaw. The Pacific crevalle jack has 21 to 27 gill raker
Gill raker
Gill rakers in fish are bony or cartilaginous processes that project from the branchial arch and are involved with filter feeding tiny prey. They are not to be confused with the gill filaments that compose the bony part of the gill. Rakers are usually present in two rows, projecting from both the...
s and 24 vertebrae. There are significant differences in the development of hyperostosis
Hyperostosis
Hyperostosis is an excessive growth of bone. It may lead to exostosis. It occurs in many musculoskeletal disorders.-See also:* Infantile cortical hyperostosis* SAPHO syndrome* Hyperostosis frontalis interna...
between this species and C. hippos.
The Pacific crevalle jack is a bluish green to bluish black dorsally, fading to a silvery white or golden shade ventrally. Juveniles are generally lighter in colour, also possessing five dark vertical
Vertical direction
In astronomy, geography, geometry and related sciences and contexts, a direction passing by a given point is said to be vertical if it is locally aligned with the gradient of the gravity field, i.e., with the direction of the gravitational force at that point...
bars on their sides. The fins are all white dusky with the exception of the anal fin and lower caudal fin lobe, which are white to brownish orange, with the ventral surface of the caudal peduncle also this colour. This contrasts to the bright lemon yellow anal and lower caudal fins of C. hippos. The Pacific crevalle jack also has a black spot on the base of its pectoral fins, as well as a dark blotch on the margin of the operculum
Operculum (fish)
The operculum of a bony fish is the hard bony flap covering and protecting the gills. In most fish, the rear edge of the operculum roughly marks the division between the head and the body....
.
Distribution and habitat
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
. The species ranges along the western America
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
n coastline from Lobos de Tierra Island, Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....
in the south and north to San Diego Bay
San Diego Bay
San Diego Bay is a natural harbor and deepwater port adjacent to San Diego, California. It is 12 mi/19 km long, 1 mi/1.6 km–3 mi/4.8 km wide...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
. The species is generally rare north of the Gulf of California
Gulf of California
The Gulf of California is a body of water that separates the Baja California Peninsula from the Mexican mainland...
, however El Nino events which bring warm tropical waters further north than usual transport Pacific crevalle jack and other species beyond their normal range. All occurrences of the species in San Diego Bay have been attributed El Nino events in that year. The species is also known from several offshore
Shore
A shore or shoreline is the fringe of land at the edge of a large body of water, such as an ocean, sea, or lake. In Physical Oceanography a shore is the wider fringe that is geologically modified by the action of the body of water past and present, while the beach is at the edge of the shore,...
Pacific islands including the Galapogos
Galápagos Islands
The Galápagos Islands are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, west of continental Ecuador, of which they are a part.The Galápagos Islands and its surrounding waters form an Ecuadorian province, a national park, and a...
, Malpelo
Malpelo Island
Malpelo Island is an island located from Colombia's Pacific coast, and approximately from Panama's coast. It has a land area of . It is uninhabited except for a small military post manned by the Colombian Army, which was established in 1986. Visitors need a written permit from the Colombian...
, Cocos
Cocos (Keeling) Islands
The Territory of the Cocos Islands, also called Cocos Islands and Keeling Islands, is a territory of Australia, located in the Indian Ocean, southwest of Christmas Island and approximately midway between Australia and Sri Lanka....
, and Revillagigedo Islands
Revillagigedo Islands
The Revillagigedo Islands or Revillagigedo Archipelago are a group of four volcanic islands in the Pacific Ocean, known for their unique ecosystem...
.
The Pacific crevalle jack is most common in coastal regions, although is occasionally found in more pelagic settings, with the species not known to live deeper than 350 m. In coastal waters the species prefers sandy and rocky substrates, including protected bay
Bay
A bay is an area of water mostly surrounded by land. Bays generally have calmer waters than the surrounding sea, due to the surrounding land blocking some waves and often reducing winds. Bays also exist as an inlet in a lake or pond. A large bay may be called a gulf, a sea, a sound, or a bight...
s, lagoon
Lagoon
A lagoon is a body of shallow sea water or brackish water separated from the sea by some form of barrier. The EU's habitat directive defines lagoons as "expanses of shallow coastal salt water, of varying salinity or water volume, wholly or partially separated from the sea by sand banks or shingle,...
s and harbours, where large schools of the species form. Larger individuals are often solitary, and living in deeper offshore
Shore
A shore or shoreline is the fringe of land at the edge of a large body of water, such as an ocean, sea, or lake. In Physical Oceanography a shore is the wider fringe that is geologically modified by the action of the body of water past and present, while the beach is at the edge of the shore,...
environments. Pacific crevalle jack are also common in estuaries, usually as juveniles which preferentially inhabit these environments, but also as adults that make their way into brackish waters and tidal streams. Juveniles are known to penetrate well upstream, indicating a wide salinity
Salinity
Salinity is the saltiness or dissolved salt content of a body of water. It is a general term used to describe the levels of different salts such as sodium chloride, magnesium and calcium sulfates, and bicarbonates...
tolerance.
Biology
Shoaling and schooling
In biology, any group of fish that stay together for social reasons are said to be shoaling , and if, in addition, the group is swimming in the same direction in a coordinated manner, they are said to be schooling . In common usage, the terms are sometimes used rather loosely...
fish for much of its life, forming moderate to large aggregations that can move quite rapidly. Older fish tend to be more solitary, moving offshore to greater depths. It is one of the most abundant pelagic species throughout its range, making it both ecologically
Ecology
Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...
and economically important. The species is a strong, fast swimming predator that takes predominantly small fish, as well as crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s such as prawn
Prawn
Prawns are decapod crustaceans of the sub-order Dendrobranchiata. There are 540 extant species, in seven families, and a fossil record extending back to the Devonian...
s and various other benthic invertebrates, although no detailed data on diet has been collected.
Individuals begin reaching sexual maturity
Sexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
at 67 cm in males and 65 cm in females, with reproduction thought to occur year round. There are peaks in spawning
Spawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
activity however, with these peaks reported as January–February and August in Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
and May and November in Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. The egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
s are pelagic, as are the newly hatched larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e.
Several studies on yearly growth in the species have given slightly different results, although the maximum difference between these studies is 5 cm per year. After the first year, the species is 19.02 to 20.64 cm long, after the second it is 29.86 to 32.95 cm, and its is 36.8 to 42.44 cm long after the third year. According to the von Bertalanffy growth equation
Ludwig von Bertalanffy
Karl Ludwig von Bertalanffy was an Austrian-born biologist known as one of the founders of general systems theory . GST is an interdisciplinary practice that describes systems with interacting components, applicable to biology, cybernetics, and other fields...
s that govern the species growth, the species may live as long as 12 or 15 years, or even 37 years as calculated in one study. These growth equations are generated using the fish's otolith
Otolith
An otolith, , also called statoconium or otoconium is a structure in the saccule or utricle of the inner ear, specifically in the vestibular labyrinth of vertebrates. The saccule and utricle, in turn, together make the otolith organs. They are sensitive to gravity and linear acceleration...
s, which add annual growth rings. These also show yearly periods of slow and fast growth, with August to February having the fastest growth due to the rainy season providing increased runoff and nutrient
Nutrient
A nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment. They are used to build and repair tissues, regulate body processes and are converted to and used as energy...
s to the coast. Slowest growth occurs during March to August, although one of the main spawning peaks occurs during this period.
Relationship to humans
The Pacific crevalle jack is of high importance to fisheries throughout its range, with the abundance of the species allowing for large catches by commercial fishermen. Due to the artisanal nature of many Central American fisheries, detailed catch statisticsStatistics
Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....
of the species are not kept, making it impossible to estimate total annual catches. Where these statistics are kept, however, it is apparent that it is one of the most important species in its range, with the species accounting for up to 15% of the total annual catch in Colima, Mexico
Colima, Mexico
Colima, Mexico, may refer to:*The state of Colima, one of the 32 component federal entities of the United Mexican States*Colima, Colima, capital city of that state...
. This translates as around 76 tonnes on average, just for the state of Colima. The species is taken year round by a variety of methods including trawling, fence and fixed nets, as well as hook and line methods. It is sold at market either fresh, frozen, smoked, salted
Salting (food)
Salting is the preservation of food with dry edible salt. It is related to pickling . It is one of the oldest methods of preserving food, and two historically significant salt-cured foods are dried and salted cod and salt-cured meat.Salting is used because most bacteria, fungi and other potentially...
or dried, and is also utilized as a source of fishmeal and oil. Despite the large numbers taken, the Pacific crevalle jack is considered a second or third class commercial product, fetching fairly low prices at market
Market
A market is one of many varieties of systems, institutions, procedures, social relations and infrastructures whereby parties engage in exchange. While parties may exchange goods and services by barter, most markets rely on sellers offering their goods or services in exchange for money from buyers...
. The value of the fish does change throughout its range based on local opinion of the fish.
The Pacific crevalle jack is also a major target for anglers
Angling
Angling is a method of fishing by means of an "angle" . The hook is usually attached to a fishing line and the line is often attached to a fishing rod. Fishing rods are usually fitted with a fishing reel that functions as a mechanism for storing, retrieving and paying out the line. The hook itself...
throughout its range, and can be taken by live bait as well as various lure types including surface poppers and fast retrieved metal slugs and spoons. It is generally viewed as marginal table fair
Fish (food)
Fish is a food consumed by many species, including humans. The word "fish" refers to both the animal and to the food prepared from it. Fish has been an important source of protein for humans throughout recorded history.-Terminology:...
, although bleeding the fish immediately after capture is said to improve the flavor.