Habitat/distribution: Gadiformes are mostly found in the northern hemisphere, though scattered southern species remain. They are relatively coldwater fish, rarely straying south of New Jersey in the US, and England in Europe.
Method of harvest: Trawl, longline, vertical line, and traps, depending on the exact fishery. There has been limited success with farming these fish.
Size: True Cod (from the Atlantic) are the largest, and historically could weigh over 100 pounds. Average size is now several pounds per fish.
Product Forms: typically sold as boneless, skinless fillet, though whole, gutted is a popular form as well.
Sustainability: American Atlantic stocks of Cod have been dramatically affected by overfishing, with some stocks, such as the Canadian, unable to recover even with no fishing pressure. Some stocks are coming back, but a large degree of uncertainty remains. Recently, the Gulf of Maine population was found to have been overestimated, and thus overfished. Elsewhere, Icelandic fisheries are in much better shape typically.
Cooking characteristics: Cod is the ultimate white fish, able to be frozen and thawed out repeatedly, sliced, breaded, fried, and made delicious. It has always been like this, since the days when all cod was salted or dried (or both usually).
Atlantic Cod (Gadus morhua)
Pacific Cod (Gadus macrocephalus)- Pacific Cod stocks are apparently quite healthy, and fisheries are tightly regulated (at least in Alaskan waters).