Jack Fish

Jack, also known as scads, trevally, and crevalles are marine bony fishes living in open waters. Jack is any of the species of fish belonging to the family Carangidae. The name Jack is also used unitedly in the family. Jacks are swift predatory fishes found largely in warm and tropical areas. The young jackfish tends to travel in a vast school but the older ones may be solitary. Many Jacks are appreciated for commercial and sport fishing and some species are successfully exhibited in public aquariums. Read the article below to know about different types of Jackfish like black jackfish, Jacksmelt fish, bar jackfish, etc.

[Image will be uploaded soon]

A member of the Jack Family and similar to their cousin Pompano, Black Jack are known for their black to grey fins from which their name is derived. They have jet black scutes that develop from their deeply forked short tail. Blackjack are not moderately round like their Pompano cousin, instead, they have a steep shale that makes them appear as if they have a round forehead. The whole body of jackfish is a gradient of an olive-brown to a dirty white-pewter grey colour.

Black Jackfish is also known for having a larger mouth than most of their cousins.  These fishes also have scythe-shaped pectoral fins. Their dorsal fins are splitted into two sections with one section having 8 spines whereas the other section having one spine followed by 22 rays. Balck Jacks are darker in colour and have scaly breasts.

Black Fish Diet And Size

Blackfish are predatory and carnivorous fishes. They consume a variety of fish, molluscs, and crustaceans. 

Blackfish are generally 2-3 feet and 12-24 pounds and can even reach a bigger size.

Balck Jack Fish Habitat

Black jackfish are often found in deep clean waters at the edge of the more outermost reefs. They swim around in the brackish water and sometimes hang near the deepest part of the Earth.

The black jack fish are found in the South Pacific United States, Hawaii, and warmer waters of the Atlantic such as the Caribbean lands.

Bar Jack Fish

[Image will be uploaded soon]

The Bar Jack Fish or red jack is a common species classified under the Jack family Carangidae. The Bar Jack fish is also commonly known by the following names, such as the carbonaro, red jack, blue-striped cavalla, or the passing jack. This species of Jack lives in the Western Atlantic Ocean and is engaged in recreational and commercial fishing.

Bar Jack Fish Diet and Size

The Bar Jack is carnivorous. It mainly eats fish and other kinds of seafood. Adult blackfish primarily preys on small fish, crabs, shrimps, worms, and others. Their immature counterparts generally feed on smaller food like plankton, fish larvae, etc.

The Bar Jack is significantly a large fish, growing to a recorded maximum of 27 inches and weighing almost 15lbs. But on average, the Bar Jack measures around 15 inches or less.

Bar Jack Habitat And Distribution

The Bar Jack commonly lives in shallow waters, mostly around coral reefs as around as 60 ft. They can live either in large schools or solitary. They are known to wander and not the type of fish that stays in a specific reef for too long, willing to travel to a great extent of sand before settling in another reef. These fishes are often recognized to venture into lagoons from seaward reefs, favouring the sandy substrates while in shallow water.

The Bar Jack is found throughout the west of the Atlantic ocean. Ranging from New Jersey and Bermuda in the north to Venezuela and possibly south of Brazil. The largest populations of Bar Jack Fish are located in the Gulf of Mexico and the West Indies.

Jacksmelt Fish

[Image will be uploaded soon]

The Jacksmelt fish, Atherinopsis californiensis, is a member of the silverside family Atherinopsidae which includes Grunion. 

Ranges: Jacksmelt ranges from Yaquina Bay, Oregon to Santa Maria Bay, Baja California, Mexico. 

Habitat: The Jacksmelt fish are typically found in estuaries, bays, canopy, sandy beaches, and along the seashore. Juvenile and adult schools in nearshore water from 5 feet to 50 feet ( 1.5 to 15 meters) depth, although they can be found in depths down to 95 feet (29 meters).

Life Span - The maximum lifespan of Jacksmelt fish is 9 - 11 years.

Jacksmelt Size (Length and Weight): The maximum length of Jacksmelt measured is 19.3 inches fork length (494 mm) weighing 0.57 kg (1.26 pounds); however, a 22-inch (559 mm) fish were reported. 

Prey: The Jacksmelt fishes are omnivorous that feeds on invertebrates, small fish, algae, and detritus.

Predators: The Jacksmelet is a group of a variety of species including game fish, marine animals, and birds.

Fishery: The Jacksmelt fish do not support commercial fishing, instead they are caught incidentally or as a bycatch by round haul targeting coastal pelagic species and hook-and-line boats fishing nearshore.

Big Eye Jack Fish

[Image will be uploaded soon]

The bigeye jack, also known as the bigeye trevally, is a species of extensively large marine fish classified in the jack family Carangidae. The big eye jack is distributed throughout the tropical waters of the Indian and Pacific Oceans, ranging from South Africa in the west to California and Ecuador in the east, including Japan in the north and Australia to the south. The big eye trevally is best characterized by its different colour, having a dark second dorsal fin with a white tip on the lobe, and also retains a small dark spot on the operculum. The big eye jack is known to enlarge to a length of 120 cm and 18 kg.

The big eye trevally is commonly found in large slow-moving schools during the day, becoming active during the night when it feeds, taking a variety of fish, crustaceans, cephalopods, and other invertebrates. 

The sexual maturity of this species is reached at 42 cm, with offspring occurring in large accumulations at different periods throughout its range, generally between July and March. The bigeye trevally is moderately important to fisheries throughout its range, and being highly important to some artisanal fisheries. These fishes are rated as fair to good table fish. The species is also considered a good gamefish, taken by delusion, harass and penetrate throughout its range.

Interesting Facts 

• Jack crevalles are coloured greenish-blue or bluish-black on their dorsal region and silvery-white to yellow-gold on their ventral region.

• The maximum size of the crevalles jack is 55.1 pounds (25 kg) and 39.8 inches. They are most common at 23.3 inches ( 60 cm). After an adolescent reaches a size of 1.97 inches (5.0 cm), its growth rate increases.  

• The Jackfish has a carnivore's feeding habits, which implies that it preys on other animals.

• Fishermen target jackfish for both commercial and recreational purposes.

• The jack fishes grow more than three feet in length, though they are more commonly one and two and a half feet long. 

• Jackfish feed during the day and eat a variety of fish and invertebrates.

• The jack fishes are not domesticated by humans in any way.

• The IUCN listed Jack species as Least Concern.

• In sport fisheries, people target jack fishes for their powerful swimming.