The yellowtail horse mackerel (''Trachurus novaezelandiae''), also known as the yellowtail scad, is a jack in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Carangidae The Carangidae are a family of ray-finned fish which includes the jacks, pompanos, jack mackerels, runners, and scads. It is the largest of the six families included within the order Carangiformes. Some authorities classify it as the only family ...

found around

Australia Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. With an area of , Australia is the largest country by ...

and

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island coun ...

at depths to 500 m. Its length is up to . The yellowtail scad is the only member of the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

genus ''Atule'' and is distinguished from similar species by a well-developed adipose eyelid and finlet-like extensions of the last rays of the

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal c ...

and

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as see ...

s. It inhabits

coastal The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in ...

areas such as

bay A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a gulf, sea, sound, or bight. A cove is a small, circular bay with a na ...

s and

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of Colony (biology), colonies of coral polyp (zoology), polyps held together by calcium carbonate. Most coral reefs are built from stony corals, wh ...

s, preying on small fishes and

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapoda, decapods, ostracoda, seed shrimp, branchiopoda, branchiopods, argulidae, fish lice, krill, remipedes, isopoda, isopods, barnacles, copepods, ...

s. The yellowtail scad is an important component of

fisheries Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life; or more commonly, the site where such enterprise takes place ( a.k.a. fishing ground). Commercial fisheries include wild fisheries and fish farms, ...

throughout its range, taken by a number of netting and hook-and-line methods. It is a prized food fish in some regions and is cooked or preserved by a variety of methods.

Description

The body profile of the yellowtail horse mackerel is a moderately compressed, oval shape body. The yellowtail horse mackerel is very similar to the

greenback horse mackerel The greenback horse mackerel or greenback scad (''Trachurus declivis'') is a species of jack in the family Carangidae, found around western and southern Australia, and around New Zealand New Zealand ( mi, Aotearoa ) is an island coun ...

, but has 68 to 73

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

scute A scute or scutum (Latin: ''scutum''; plural: ''scuta'' "shield") is a bony external plate or scale overlaid with horn, as on the shell of a turtle, the skin of crocodilians, and the feet of birds. The term is also used to describe the anterior po ...

s, compared with 76 to 82 for the greenback horse mackerel. The coloration of the yellowtail horse mackerel is a bright olive green above, transitioning to a more golden green ventrally, before becoming silvery white on the underside of the fish. Nine to 16 faint grey bars run vertically on the sides of the fish, as well as a black spot slightly smaller than the eye on the upper margin of the operculum and adjacent shoulder region. In some parts of Australia, the Yakka are prone to the parasite

Cymothoa exigua ''Cymothoa exigua'', or the tongue-eating louse, is a parasitic isopod of the family Cymothoidae. It enters fish through the gills. The female attaches to the tongue, while the male attaches to the gill arches beneath and behind the female. Fem ...

which first eats and then replaces the tongue of the host fish. The parasite does not otherwise harm the fish and has no effect on humans. The parasite should however be removed before consumption.

Distribution and Habitat

Adult yellowtail horse mackerels are found in coastal waters and estuaries, showing a preference for waters less than deep and no cooler than . They are frequently encountered on the bottom or in midwater but are only infrequently recorded near the surface, they occur in large schools. Adults are normally recorded over rocky reefs just offshore while the juveniles prefer waters with shallow, soft substrates.

Diet

The yellowtail scad is a pelagic predator that takes a variety of small plankton and fish. The species exhibits two different feeding patterns during different stages of life, with the juveniles between 91 and 150 mm feeding mainly on crustaceans while adults over 151 mm prey almost exclusively on small fish.

Relationship to humans

This species can be sold fresh, smoked, canned and frozen; and it can be cooked by frying, broiling and baking. It is a relatively long lived species for its size, living up to 15 years, and is exploited by commercial and recreational fisheries. In

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

the catch per annum since 1997 has been between 300 and 500 tonnes but much of the catch is discarded or used as bait.

References

{{DEFAULTSORT:Yellowtail horse mackerel yellowtail horse mackerel Marine fish of Southern Australia Fish of New Zealand Taxa named by John Richardson (naturalist) yellowtail horse mackerel