Cod - Cadidae
Representatives of this family are most numerous species of Kamchatkan waters. Their distinction is 3 back fins and 2 anal fins and also a barb on chin.
Walleye pollock, Alaska рollack (Theragra chalcogramma, Rus. - mintai)
Alaska рollack differs from other cod with a typical coloring of upper part of its body with a spotted pattern; its lower jaw is protruded and a chin barb is hard to notice.
It is a most spread and numerous species in northern part of Pacific Ocean. It lives all over Kamchatka waters and main populations are eastern Okhotsk, western Bering, and eastern Kamchatkan ones.
Alaska рollack is rather a large bottom-dwelling fish that habits also in skotopelagial. Alaska рollack can be as long as 85 cm (34") and as heavy as 4 kg (8.8 lb). In commercial catch 4-8 years old fish prevail, fish older than 8 years is met rarely. Alaska рollack becomes mature in age of 3-6 years.
Fall-winter-spring spawning is typical for Alaska рollack which is later in northern parts of its range. Seasonal migrations connected to definite stages of their life cycle are typical. In prespawning period mature Alaska рollack get together near reproduction areas in depth of 200-300 meters (650-1000 ft). As their reproductive products get ready, Alaska рollack moves to shelf and to the end of common spawning period individuals get up to 40-50 m (130-160 ft). When spawning time is over, Alaska рollack gradually leaves spawning grounds and settles broadly in minimum depths in the shelf and also above ocean depths to 2-4 km (1.2-2.5 m). By vertical distribution in water column it occupies intermediate position between bottom and pelagic species of fish. During a day it can change environment for hundreds of meters from near bottom horizons to very top water layers.
Pacific cod, Grey cod (Gadus macrocephalus, Rus. - treska)
It has elongated body, big head with big mouth and a barb on the lower jaw. It has silver-brown coloring, dark back with brownish spots and streaks, and white belly.
In Kamchatkan waters it can be found in area from cape Khairyuzovo in Okhotsk sea to Anadyr gulf and the Commander Islands inclusive. There are mass approaches and catches in May-June in area of the Ozernaya river and second half of summer near north-western coast of the peninsula. Near south-eastern coast, in Avachinsky and Kronotsky gulfs, in June-August; in Olyutorsky gulf in August. Cod spawns in March-April.
In summer cod fattened in off-shores of 20-60 m (66-200 ft) depth, and in fall it moves to depths of 180-300 m (600-1000 ft) and forms dense gathering there. Cod fries can be found in small depths up to 200 m (650 ft). However cod can live in depth ranging from 10 to 800 m (33-2,600 ft).
Water temperature in its environment is 0-4С (32-39F)
Cod can be as long as 115-120 cm (45-47") and as heavy as 18-20 kg (40-44 lb). In commercial catch there are fish of 50-80 cm (20-32”) and 2-5 kg (4.4-11 lb).
Cod is a predator. It eats fish like Alaska Pollack, herring, capelin and others, and also invertebrates like crabs, worms, and shellfish.
Saffron cod, Wacha cod (Eleginus gracilis, Rus. - navaga)
Saffron cod has terete body, covered with small scales. It’s head and back are dark-green with pale-yellow belly, sometimes golden. Spawning cod has especially bright coloring.
In Kamchatkan sea waters it habits almost everywhere from Penzhina bay to the western part of Bering sea. It is most numerous near mouths of large rivers. Sometimes it enters their lower reaches. It can reach 53 cm (21”) of length, 1.1 kg (2.4 lb) of weight, and age of 15 years. Regular catches have individuals of 25-35 cm (10-14”) and 2-4 years old. Saffron cod becomes mature in the age of 2-5 years. Spawning usually occur in winter time in coastal waters, gulfs, bays, near river mouths, and in desalinated waters.
After spawning cod settle in coastal waters without going far into sea. It does not form gatherings in this period.
Saffron cod is polyphage and feeds on various bottom-dwelling and pelagic crustaceans and fish. In winter after spawning it is able to eat its own roe.