Gadidae

Gadidae is a family of mostly marine fishes that includes cod, haddock, pollock, and hake. Many species are important predators and commercial food fishes.

Gadiformes: Gadiformes is the order of ray-finned fishes that includes cods, hakes, and grenadiers. Gadidae is one family within this broader fish order.
Cod fisheries: Cod fisheries are commercial and subsistence harvests of cod species. Cod harvest has shaped the economic importance of several Gadidae species.
Demersal fish: Demersal fish live and feed on or near the seabed. Many gadids forage near the bottom, though some occupy midwater habitats.
Merlucciidae: Merlucciidae is the family of hakes, a group of marine fishes related to cods. Hakes resemble cods but belong to a separate family within Gadiformes.
Atlantic cod: Atlantic cod is a large gadid fish native to the North Atlantic Ocean. It is a familiar species that exemplifies the family's body plan and ecology.
Haddock fishery: The haddock fishery harvests haddock, principally in the North Atlantic. It illustrates how a single gadid species supports regional fishing industries.
Swim bladder: A swim bladder is a gas-filled organ that helps many bony fishes regulate buoyancy. Buoyancy control supports the water-column movements of many gadids.
Lotidae: Lotidae is a family of fishes that includes the burbot and ling species. Lotids are close gadiform relatives, but are classified outside Gadidae.
Haddock: Haddock is a North Atlantic gadid distinguished by a dark shoulder mark and a dark lateral line. This close relative shows the diversity of commercially important cod-family fishes.
Alaska pollock fishery: The Alaska pollock fishery is a large commercial fishery in the North Pacific and Bering Sea. It is among the largest fisheries by catch and depends on a gadid species.

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