About Gadus macrocephalus Tilesius, 1810
Gadus macrocephalus, commonly known as Pacific cod, has three distinct separate dorsal fins, and whisker-like barbels similar to those of catfish on its lower jaw. In overall appearance, it is very similar to Atlantic cod. It is a bottom-dwelling species found mainly along the continental shelf and upper continental slopes. Its distribution circles the rim of the North Pacific Ocean, spanning from the Yellow Sea to the Bering Strait, along the Aleutian Islands, and south to approximately the area around Los Angeles, and can be found at depths down to 900 meters (3,000 feet; 500 fathoms). This species can grow up to 1 meter (40 inches) in length and reach a maximum weight of 15 kilograms (33 pounds), and it forms extremely large schools. Molecular genetic research strongly indicates that Pacific cod and Greenland cod (Gadus ogac) from the Greenland–Arctic Ocean region are actually the same species, meaning G. ogac should be classified as a junior synonym of G. macrocephalus. Currently, both ITIS and the Catalogue of Life list Gadus ogac as a synonym of Gadus macrocephalus.
