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Navaga fish identification, its habitats, characteristics, fishing methods.
Navaga is a relatively small fish widely distributed in the Arctic Ocean in the White, Barents and Kara Seas. Navaga fish usually occur off the coast at shallow depths, along shores with soft bottoms, close to the ice and on the continental shelf, during the pre-spawning period in masses approaches to coast and comes with tidal currents into the rivers. In winter they live in nearshore waters, where spawning takes place in November - January under an ice on depth of 8-10 m between the Islands, in places with strong currents and stony or sandy ground. They are often found in estuaries and can enter fresh water in rivers. In summertime they return to open waters. They feed on crustaceans and benthic animals, also on small fish. Adult size is usually 25-35 cm, but White Sea fish are smaller, 15-25 cm. Navaga is tasty fish commercially fished mainly in the wintertime in the bays of the White Sea.
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Navaga, Eleginus navaga, also known as Arctic saffron, Atlantic navaga, Wachna cod, Morue arctique in France, Bacalao Del Artico in Spanish, Навага Северная in Russian, is a relatively small species of fish in the cod family Gadidae, genus Eleginus. It inhabits the European arctic and subarctic waters of the Pechora (Southeastern Barents Sea), White and Kara Seas, off the East Murman, from the Kola Bay to the Ob river estuary, including Dvina, Onega and Mezen bays of the White Sea and Cheshskaya Inlet, Arctic shores of Asia and North America, south to Bering Sea.
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Description
Navaga have slender and rounded body, depth is 1/6th, with a rather long head, 1/4th is of body length; snout is 1/3rd, viewed from above rounded, but running to a rather sharp point when viewed from the side. Eye is 1/6th in head; interorbital space is 1/5th; barbel small, equal to pupil; scales are small, 157 transverse rows above lateral line from gill opening to first rudimentary caudal rays. Lower jaw included, the fleshy snout projecting beyond the maxillary, its length slightly greater than that of the snout; tip of maxillary on a vertical with the front of the pupil; articulation of mandible with quadrate bone on a vertical running midway between pupil and posterior edge of eye; teeth all slender and curved backward, those in upper jaw in several irregular rows, the outer row regular and with slightly larger teeth; teeth in lower jaw in a single row except in front where they are in a double row; teeth on vomer few and about the size of the smaller teeth in the upper jaw.
Gill rakers moderate, the longest not quite equal to diameter of pupil; caudal peduncle compressed, its depth equal to diameter of eye, 1/6th of a head; vent under front of 2nd dorsal; pectoral fin not reaching vent, its length If times in head; ventrals reaching halfway to vent, the 2nd ray moderately produced; first dorsal highest; distance between 2nd and 3rd dorsals twice distance between 1st and 2nd; caudal fin very slightly concave; 3rd ray of 2nd dorsal midway between tip of snout and base of middle caudal rays.
Key characters
Expanded parapophyses swollen and hollow, beginning on about vertebral centrum 5, containing outpouchings of the swim bladder. Only one pair of parapophyses on fifth vertebra, short and not swollen. Lateral line continuous to about the origin of the second dorsal fin. Head with no lateral line pores.
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12 to 16-14, 21-18, 22 Dorsal fin rays
19, 23-19, 26 Anal fin rays
57-60 Vertebrae
19-31 gill rakers
Max. Size: 42cm, usually 15-23cm
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Color somewhat mottled, grayish brown with brownish or dark spots on back above, light silvery below; the 3 dorsals and caudal dusky and edged with white; pectorals uniform dusky; ventrals but slightly dusted with black; anal with a few punctulations at their anterior ends; peritoneum pale.
There is a very little difference in the skulls Navaga and Pacific tomcod, Microgradus proximus. There is no difference in the neural spines of the vertebrae. The transverse processes of the vertebrae in Pacific tomcod are flattened and platelike, while in Navaga, Eleginus naraga they are club-shaped, narrow at base where they leave the centrum, but expanding into a rounded hollow bulb at the distal end. The Navaga is a close relative of the Saffron cod (Eleginus gracilis), a Pacific sister species.
Habitats
Lives in the coastal, sublittoral zone of the White Sea and Arctic coasts of Europe where it reflects a broad adaptation to the ecological conditions of the Arctic. It is found at shallow depths, salt and brackish waters, along shores, inshore, especially in bays with soft, muddy bottoms, close to the ice and on the continental shelf. It sometimes forms large schools under the ice. It is often caught in greatly freshened and at times completely fresh water, entering the mouths and tidal zones of rivers and traveling upstream, in winter under ice. Not found in the open sea or at great depths. This species does not undertake extensive migrations except for daily feeding.
It feeds mainly on crustaceans and worms, but eats small fishes as well, including stickleback, capelin, sandeels, saika, small cod, flounder, and navaga, which play the greatest role in the sustenance of larger navaga. In summer, with the rise of water temperature to 10°C and higher, they eat very poorly. It is in turn eaten by a wide range of larger fishes and Arctic mammals, and young are preyed upon by sea-birds. Staple food is amphipods, mysids shrimp, small fish and worms.
Spawning:
In the pre-spawning period in the winter, it gathers in great numbers coming close to shores, and enters the mouths and upper parts of rivers into areas with tidal currents. However, for spawning they move from the shores and river mouths in sea water to greater depths of 8-15 m. Spawning occurs only in December-January, during about 15 days, in channels between islands or in depressions between the shore and shallow banks with strong tidal currents and stony or sandy or rocky ground.
Navaga reaches sexual maturity in the age of 2—4 years. Females produce between 6 000 and 90 000 eggs per year. Eggs are benthonic, demersal, sink to the sea-bed, but are not adhesive, not sticking to a ground. Development of the eggs occurs only in salt water; they perish in fresh water. Duration of hatching is 4 months. Under normal temperature conditions, the main mass of spawning Navaga consists of 2 to 4 year- olds whose dimensions are: 18 cm total length at 2 years, and 21 cm at 3 years.
Usual sizes in the White Sea are 15-23 cm, but the species reaches 35 cm and more; in Mezen Bay at the western shores of Kanin Peninsula, it attains the greatest size (to 40-42 cm) and age (7 years). Apparently, in the other bays, local races or schools are formed.
Fishing Methods:.
Navaga is a tasty fish, catching under ice during the approach to the Bank for spawning, mainly from November to January. It is commercially fished by the Soviet fleet in the White Sea with a type of net used in northwestern Russia and partially on hook and line. The industrial catch takes place during mass gatherings for spawning beneath the ice, near shore. It begins in November and the greatest catches coincide with the peak of spawning in January, after which hungry, post-spawning Navaga are caught and the catch figure drops rapidly. Main fishing grounds are Dvina, Onega and Mezen bays of the White Sea and Cheshskaya Inlet.
Cod Recepies
Cod meat is white in color, is moist and lean, medium- to firm-textured, and delicately flavorful with a mild taste. Tender, thick fillets with large flakes that "gape" (separate) when cooked. It is a good source of low fat protein, phosphorus, niacin, and vitamin B12 with a mild flavor and a dense, flaky white flesh. Cod livers are processed to make cod liver oil, an important source of vitamin A, vitamin D, vitamin E and omega-3 fatty acids (EPA and DHA).
Cod is excellent for poaching, broiling, baking, braising, and frying. A popular main ingredient in chowders, which are creamy and binding enough to support the big flakes of meat that fall apart when cooked. Whole cod are often stuffed and baked. Heads and bones make fine soup stock.
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