Haddock is a member of the cod family. It is easy to recognize; it has a black line that runs laterally along its white skin. There is also a dark spot above its pectoral fin, often described as a thumbprint. Haddock live in the American and European waters of the Atlantic Ocean.
Haddock like deep, cool water with temperatures between 35 and 50 degrees F. Adult haddock are most likely found at depths of 150 to 450 feet and do not like shallow water, so you rarely find them in bays or river mouths. They migrate seasonally to accommodate their habitat.
Their diet consists of small crabs, sea worms, clams, starfish, sea cucumbers, sea urchins and occasionally small fish and squid. Rarely will a haddock exceed 20 to 24 inches in length, 5 pounds in weight or live to be 10 years old. Spawning peaks in March and April and an average-sized female will produce approximately 850,000 eggs. Larger females are capable of producing up to 3 million eggs each year. Haddock is fished year-round using Danish seine nets, trawlers, long lines, and fishing nets.
Fresh haddock has a fine white flesh and can be cooked just like its relative, cod. Freshness of a haddock filet can be determined by how well it holds together-it should be firm and the flesh should be translucent. Separating flesh and a chalky white look indicate that the fish is not fresh.
Young, fresh haddock and cod filets are often sold as scrod in New England. This is confusing at first, but simply relates to the size and age of the fish.
Haddock is considered a premium whitefish, an excellent source of protein with vitamin B12, pyridoxine, selenium, sodium and potassium. It is also an excellent source of protein and contains a healthy balance of sodium and potassium. Overall the meat is extremely lean.