Cod is the world's existing fish in the large size, long life, the oldest kind of fish, so far there are more than 200 million years of history, called the "living fossil in the water". The world's existing sturgeon 2 families, 6 genera and 26 species. Sturgeon is a low-fat, high-protein meat, containing 3-5 times higher than other fish Omega-3 unsaturated fatty acids and hematopoietic vitamins - folic acid (Folicace), sturgeon cartilage and spinal cartilage containing chondroitin sulfate, anti-cancer and strengthen the immune effect is better than the shark cartilage powder. Its meat without intermuscular spines, edible rate is high, can be used for sashimi, hot pot, smoked, canned and other food, is the international market best-selling high-grade products. Artificially farmed live sturgeon, the meat quality is superior to salmon eaten raw fresh, tender, smooth, crisp, superior to lobster. Sturgeon body is cartilage, its cartilage, fish skin, fins, fish liver, fish intestines, fish belly can be made into dozens of different styles of famous dishes. Sturgeon cartilage has anti-cancer and calcium effects, sturgeon bones can be boiled into a delicious sturgeon bone soup. Sturgeon kiss and nasal cavity and other parts rich in collagen. Sturgeon eggs can be processed into fish roe sauce, which is the best-selling commodity on the international market. Because of its gray-brown eggs, commonly known as "black gold", "black pearl", the price of roe sauce makes the sturgeon industry has become one of the world's most profitable industry. Sturgeon skin with tough, durable and beautiful features, can be made into high-grade leather. In addition, sturgeon gills have a special effect of heat detoxification; sturgeon oil has the special effect of treatment of burns. In short, the sturgeon can be said to be full of treasure, edible, medicinal, but also for health care products.
Cod cluster is very strong, is a cold water migratory offshore fish, most of the life in the Pacific Ocean, the Atlantic Ocean, the northern water temperature of 0 ℃ ~ 16 ℃ of the sea water, and the scope of activities is usually in the distance from the surface of the water 1500 meters of the deep sea; where the cold season water temperature is not as cold as the shallow waters.
The world's most unafraid of the cold is the Antarctic cod. In the cold, icy waters of the Antarctic, it is able to freeze without freezing. It turns out that the blood of this fish contains an ingredient called glycosaminoglycan, which is similar in effectiveness to antifreeze in cars.
The Antarctic cod lives in the colder waters of the Southern Ocean, and is even found near the Ross Ice Shelf, which is located at 82°S. It is about 40 centimeters long and weighs a few kilograms, with a short, thick, silvery-gray body with slight dark brown spots, a large head, round mouth, thick lips, and grayish-white blood with no hemoglobin. As an edible fish, it has tender white meat, delicious flavor and high nutritional value. Its unique physiological function is resistance to low temperatures, so in addition to the commercial development of Antarctic cod as an important resource, its anti-freezing function is also highly valued.
Fish physiology research results show that the general fish in -1 ℃ on the frozen "popsicle". Antarctic cod can be in -1.87 ℃ temperature active life, as if nothing happened to swim around. Originally, in the blood of Antarctic cod there is a special biological chemicals, called antifreeze protein, is this antifreeze protein in the role.
Anti-freeze protein has an anti-freeze effect because its molecules have an extended nature, as if there is a surface area on its structure that is very easy to interact with water or ice, thus lowering the freezing point of water and thus preventing the freezing of body fluids. As a result, antifreeze proteins give Antarctic cod an amazing resistance to low temperatures.
Cod is usually referred to as the cod-shaped fish, is a large family of the marine world, is known to be more than 500 species, is the main object of marine fisheries. 1996 global cod catch amounted to 10.71 million tons, accounting for 12% of the total marine fisheries production. The main fishing species belong to the cod family, hake family and long-tailed cod family. It is known that there are more than 50 species of cod in the world, most of which are distributed in the continental shelf waters of the northern Atlantic Ocean, and the important species are Pacific cod, Atlantic cod, haddock, blue whiting, green cod, cod, Norwegian long arm cod and pollock, and so on.
Morphological features of cod
Cod belongs to the family Codidae.
Local names: big head green, big mouth fish, big head fish, mintai fish, mizoguchi, broad mouth fish, big head fishy, stone gut fish.
Morphological features: body extension, slightly flattened sideways, tail backward tapering generally as long as 25 to 40 centimeters, weight 300 to 750 grams. The head is large, the mouth is large, the upper jaw is slightly longer than the lower jaw, the neck has a tentacle, the whisker length is equal to or slightly longer than the eye diameter. Both jaws and the plow bone are equipped with fluffy teeth. The body is covered with fine rounded scales that are easily removed, with a distinct lateral line, three dorsal fins, two anal fins, and all fins are free of spines and composed entirely of fin rays. The head, dorsum and sides of the body are grayish brown with irregular dark brown markings, and the ventral surface is grayish white. The pectoral complex is light yellow, and all other eels are gray. There are three dorsal fins, two anal fins, and a truncated caudal fin. Cod meat is thicker and coarser, in the shape of garlic cloves, with a fresher flavor and fewer spines.
Origin, season: distributed in the North Pacific Ocean. In China, it is produced in the Yellow Sea and the northern part of the East China Sea. The main fishing grounds in the northern Yellow Sea, Shandong high angle southeast of the east and south of the ocean island and the southeast sea area. Fishing season has winter and summer floods, winter flood is December to the following February; summer flood for April to July.
Economic value: it is a cold-water demersal fish, one of the marine economic fish produced in the northern coast. Cod per 100 grams of meat containing 16.5 grams of protein, 0.4 grams of fat. Its meat is white, fine and tender, clear mouth is not greasy, many countries in the world to the cod as the main edible fish. In addition to fresh food, but also processed into a variety of aquatic foods, in addition to cod liver and high oil content, rich in vitamins A and D, is the raw material for the extraction of cod liver oil.
Cod's diet
Cod is omnivorous, known for its large appetite, favorite food is herring, but when hungry, flounder, shrimp, squid, starfish, sea fans, as long as the things that will move, anything to eat. It eats a lot and therefore grows fast, increasing its weight at a rate of 1.5 times per year and growing to 1 meter in about 10 years or so.
Cod is a deep-sea cold water fish, generally living in the depth of 50 meters above the deep sea area. In China's Yellow Sea, the Bohai Sea and the northern coast of the East China Sea, fishermen and more to describe the physical appearance of the fish called "big head fish", "big head fishy" and so on.
Cod is mostly pinkish brown or grayish brown in color along the coasts of China, with irregular dark brown patches or stripes on the back. The head is large (commonly known as "big head fish" from this) and the body extends the lateral compression, the tail is small and wedge-shaped. The mouth is wide and slightly slit, the lower jaw is short, and there is a tentacle under the front end of the lower jaw (this is also one of the main features that distinguish it from Pacific cod), and there are downy fine teeth in the upper and lower jaws and between the plow bones. The dorsal fin is single and unattached in the form of a lateral triangle, while the ventral fin is placed in the throat area, and the scales are small and the lateral line is not obvious. Most inhabiting swim in the deep sea bottom, generally do not do migration, but only the annual early winter reproductive period (beginning in early November each year) to the offshore coast for a short period of migration.
Cod is a deep-sea carnivorous and ferocious fish, mainly feeding on small fish, shrimp and invertebrates. Often live in water depths of more than 50 meters, around the sandy texture of the sea wrecks or the seabed larger reef area. Individuals mostly in about 30 centimeters, the largest individual can reach more than 60 centimeters, weighing more than ten kilograms. Before the 1970s, it was the main economic fish in China, mostly caught by purse seine fishing or longline fishing. Because of the sharp decline in production in recent years, it is difficult to form a large fish season and gradually give up. Now the anglers use boat fishing sinking type fishing method, for the above coastal areas of the anglers in winter and spring fishing one of the main object of the fish.
Haddock
Haddock, also known as "North Atlantic cod", belongs to the cod family.
Morphological features: Haddock has a number of features that help to distinguish it from other cod, such as its high, pointed first dorsal fin, black lateral line, and dark "thumbprint" above the pectoral fins. In addition, the small tentacles on its lower jaw are shorter than those on its upper jaw. They usually congregate in large groups near the bottom at depths of 40 meters or more, averaging less than 2.27 kilograms and generally reaching a maximum of about 6 kilograms.
Origin: North Atlantic.
Fishing method: Fishing for cod in the ocean can be done by beach casting from the shore, or by natural bait on rocks, piers and breakwaters, or from a boat with a natural bait or a hair hook, a draw hook, or an attention-grabbing spoon-shaped bait attached to a baited hook. River cod, a freshwater fish in the cod family, is a slow-moving fish that feeds mainly at night and can be fished in shallow water with stationary bottom fishing.
Tackle: When fishing for marine fish from the shore, try a 3.7-meter beach casting rod with a powerful reel, 13.6 kilograms of nylon line, hooks of size 2/0 to 8/0, and a bullet-shaped lead weight or a bottom-grabbing lead weight. When fishing for saltwater fish from a boat, use a 13.6 leaning-over-me-class boat fishing rod with a 4/0 to 6/0 power reel, 3.6 kg of wire leader or nylon line, and a 2/0 to 8/0 hook. When fishing with natural baits and hair hooks, use a bullet-shaped lead weight. For river cod, try a 3- to 3.7-meter bottom-casting straight-sense rod with a fixed-axis reel, 2.7 kilograms of monofilament bus line, and size 10 to 14 hooks.
Bait: There are a wide variety of natural baits that work well for walleyes, including many invertebrates such as mussels, sea worms, clams, razor clams and squid. As for baitfish, both filleted and whole fish are worth trying, especially oil-rich fish such as herring, mackerel, kibble herring and sardines. Among the artificial baits, lead-head hooks, metal hooks and plastic jellies are all effective. A bunch of orange or white feather hooks on size 5/0 hooks make an excellent boat bait. River cod will eat whole strings of large worms or minnows.
The haddock is a demersal marine fish found in the North Atlantic Ocean, and has been commercially harvested for a long time as a heavily consumed fish. Haddock is easily recognized by the black lateral lines on the white side. Haddock are commonly found at depths of 40 to 200 meters, and juveniles prefer shallower waters than adults. They generally live near the continental shelf or in cooler waters away from the coast, where water temperatures range from 2 to 10 degrees Celsius (36° to 50° Fahrenheit).
In general, haddocks are not adept long-distance swimmers as benthic fish, and regional migrations over the course of a year are uncommon, but short- to medium-distance food-seeking migrations sometimes occur. Adult haddock are not as habitually migratory as younger haddock, but all haddock, young and old, have seasonal migrations. The diet of haddock varies according to size, season and region. For example, small fish and shrimp are the main diet of young haddock, while larger individuals consume other fish, especially in spring and summer. However, during the winter all sizes of haddock generally feed on benthic invertebrates such as worms, small molluscs, sea serpent tails and sea urchins.
Haddock is a marine fish found on both sides of the North Atlantic Ocean. Haddock is a popular food fish and is fished widely commercially. Haddock consists of a black easily recognized lateral line running along its white side, not to be confused with pollock which has opposite, blank lines on the black side and a particularly dark stain on the upper pectoral fin.
Haddock is usually found at depths of 40 to 133 meters, but has a range as deep as 300 meters. It thrives at temperatures of 2° to 10°C (36° to 50°F). Juveniles prefer shallow water and larger adults deeper water. Normally, adult haddock do not engage in long migratory behavior like fry, but seasonal movements are known to occur across all ages. Haddock feed primarily on small feeding invertebrates, although larger members of the species may occasionally consume the fish.
Haddock growth rates have changed significantly over the past 30 to 40 years. Currently, growth is rapid, and when haddocks reached their adult size earlier was noticed much earlier. However, the extent to which this fry contributes to the regenerative success of the population is unknown.
The haddock is in a biologically dangerous state and a fishery closure has been necessary since 2003. The report suggests that recovery of the cod stock will take at least five to six years, while a 12-year closure will be biologically necessary. As the most important commercial species of cod and haddock in Europe, the Baltic Sea and the North Sea are the main fishing grounds. In 2002, the catch quota of cod in Europe was 149,000 tons, with 41,000 tons, or about 25%, in the North Sea; and the quota of haddock was 107,000 tons, 77,000 tons of which belonged to the catch quota of the North Sea. However, the stocks of both species have declined dramatically. Getting the cod back to healthy reproduction could require 100,000 tons of spawning stock. As a result, the Director of Marine Scotland, Robin Cook, has proposed to the European Fisheries Commission a zero-quota closure until 2015. This has been strongly opposed by all UK and Scottish operators who depend on the resources of the North Sea.