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Fish & Other Seafood

Beche De Mer
(Sea Cucumber)

Also known as Scad, Cowanyoung and Horse Mackerel. 

See Cowanyoung

The Common Jack Mackerel has an elongate body and a forked caudal fin. The scales in both the curved and straight parts of the lateral line are enlarged and scute-like, but may be overgrown by smaller scales in larger individuals. An accessory lateral line runs close to the base of the dorsal fin as far posteriorly as the fifth to tenth dorsal fin ray. The first dorsal fin is shot-based with eight spines. The second dorsal fin is long-based with the terminal ray being enlarged and slightly separated from the rest of the fin.

The species is dark blue-green above and silver to grey below. There is a prominent black blotch on the rear of the operculum.

The Jack Mackerel, greenback horse mackerel or greenback scad, Trachurus declivis, is a species of jack in the family Carangidae, found around southern Australia, and around New Zealand, from the surface to depths of 460 m. Its length is up to 64 cm.

Its common name derives from the legend that other smaller species of fish could ride on its back over great distances.

The greenback horse mackerel is similar to the koheru but has a blunter snout, larger eyes, and a line of 71 - 89 large and conspicuous bony scutes along the entire lateral line. They are commonly found near the bottom, in midwater and occasionally at the surface over the continental shelf. They form pelagic schools for most of the year but may move close to the sea bed during winter. They are generally found at less than 300 m water depth with temperature less than 16° C. Juveniles inhabit coastal and estuarine waters although they may sometimes be found offshore.

They feed mostly during the day, mainly on krill and other planktonic crustaceans, hatchetfishes (Sternoptychidae) and lantern fish (Myctophidae) at the edge of the continental shelf.

It is an important commercial fish.

Good Marlin bait.

This species looks similar to the Yellowtail Scad. The Common Jack Mackerel is longer and more slender than the Yellowtail Scad and has a longer accessory lateral line (only reaches to below the first or second dorsal fin ray in the Yellowtail Scad).

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