Snappers are a family of perciform fish, mainly marine but with some members living in estuaries, and entering fresh water to feed. Some are important food fish. One of the best known is the red snapper.

Snappers are found in the tropical and subtropical regions of all the oceans. They can grow to about a meter in length. Most feed on crustaceans or other fish, though a few are plankton-feeders. They can be kept in aquaria, but mostly grow too fast to be popular aquarium fish. They live at depths of up to 450 m.

About 100 species of snapper are currently recognised, divided into about 16 genera. A very large number of fish species have "snapper" in their common name; most but not all of these are members of the family Lutjanidae. Almost all the 60 or so species in the genus Lutjanus have common names including the word "snapper".Commonly called Mangrove Jack within Australia, the Mangrove red snapper (Lutjanus argentimaculatus) is an explosive and powerful sport fish that is renowned for its superb eating and fighting qualities.

Coloration of the Mangrove Jack ranges from burnt orange, to copper, to bronze and dark reddish-brown, depending on its age and environment. Younger fish caught in estuarine areas are often darker than older fish taken from offshore reef areas, and exhibit lighter vertical bands down their flanks.

Lutjanus argentimaculatus is found in the Indo-Pacific region from Australia in the south to Japan in the north, and as far west as the eastern coast of Africa. Distribution within Australia is largely centered on the northern half of Australia, spreading from northern New South Wales into northern Western Australia.

Mangrove snapper

As its name implies, the Mangrove Jack is commonly found in mangrove-lined estuarine systems although is known to migrate to offshore reefs in order to spawn. As ambush predators, `Jacks' often dwell around mangrove roots, fallen trees, rock walls, and any other snag areas where smaller prey reside for protection. For fishermen, the telltale sign of a hooked Mangrove Jack is the explosive run for cover once the bait (or lure) is taken. Many fish (and again, lures) are lost once they reach the protection of the snags as a result of their initial burst of speed. As they mature, Mangrove Jacks move into open waters, sometimes hundreds of kilometers from the coast in order to breed. These larger fish are sometimes caught by bottom-fishers with heavy tackle, though they still remain difficult to land due to their speed and proximity to sharp reef bottoms.

The Mangrove Jack is a highly regarded table fish with firm, sweet tasting, white flesh. While often a nuisance species when targeting the infamous Barramundi, many fisherman rate the eating qualities of the Jack higher than its more famous neighbour. In reef areas, Mangrove Jack are sometimes confused with red bass (Lutjanus bohar), a known carrier of Ciguatera toxin. They are however easily distinguishable by the large deep pit in front of the eyes of the red bass.