Is canned fish like salmon or sardines cooked?

Yes. Most are steamed; some are fried or hot-smoked.

(from http://www.epicurious.com/gourmet/good_living/sardines and http://www.washingtonpost.com/wp-dyn/articles/A54441-2004May25.html)

Sardine is more of a generic term that is applied to any soft-boned, small fish with a fatty flesh. Herrings, sprat, and young pilchards are some of the names of the fish that are called sardines. They are iridescent, silvery, and swim in huge schools near the surface. They can be salted, smoked, or canned in oil, tomato sauce, or mustard sauce. Some are packed into cans as is; others are skinned, boned, or sold as fillets. They are best grilled, broiled, or fried. The name probably comes from young pilchards caught off the coast of Sardinia, which were one of the first fish packed in oil. I looked in my "Joy of Cooking" (published in 1964) for their suggestions about sardines. They say, "Pacific sardines are almost twice as large as the Atlantic kind, and both are bigger than the type of pilchards originally caught off Sardinia. Anchovies are even smaller sardines. When smoked, sardines are referred to as sprats. Treat fresh sardines as for Smelts." Then they offer a recipe, as follows: "If you want to present canned sardines in an interesting way, skin and bone, 12 canned sardines. MASH 6 of them with: * 1 (teaspoon) tsp minced onion * 2 tsps butter * 1/2 tsp prepared mustard * 1 tsp lemon juice * Spread 6 narrow toasts with this mixture. Place a whole sardine on each toast and run under the broiler. Before serving garnish with: * Finely chopped fennel * A grating of black pepper" My former husband loved canned sardines, and would open a can, plop a fat sardine on a saltine cracker, and eat the whole can that way! I always left the room to avoid the stench! I have eaten the bones from sardines (love the hot mustard flavor), however I always pick the round bones out of canned salmon before cooking it. The person that sent the above paragraph have their answer but my answer is a bit different. The canning process heat treats the food. With canned salmon and sardines the bones have been greatly softened and can be safely eaten. The high heat sterilization process softens them to the point where they can be easily mashed and blended into salmon salads, casseroles, and other delicious meals. There is no waste in canned salmon -- the liquid, skin, and bones are all edible and supply important nutrients such as calcium and phosphorus. As a kid, I loved picking them out and eating them as my mother opened the cans. In our home the bones and skin are always left in. The oily skin is high in Omega 3.