This species is commonly found in the Pacific Ocean around the Japanese archipelago and the East China Sea off Taiwan.

HABITS:

Occurs from 10 to 50 m depths, often on rough grounds, but also on softer bottoms. Also inhabits reefs. Adults migrate into shallower parts of their depth range to spawn in late spring and summer; juveniles occur mainly in the shallower areas. The species feeds on benthic invertebrates, including echinoderms, worms, mollusks and crustaceans; also on fishes.

SPAWNING:

The red sea bream is protandrous, being functional male at the age of one year but reversing to functional female in later years. Both sexes are present during the third year of life at the size of 40-50 cm and 1.4-2.3 kg. Fish of this size from either the capture fishery or from culture cages are used as brooders. The spawning season is between late January and early April. Mature males can be stripped of milt throughout the breeding season. A female responds positively to hypophysation if it yields eggs 0.5 mm in diameter when sampled with a vinyl section tube inserted into the genital opening. This kind of female, when injected with one IU of Puberogen/g of broodfish, ovulates successfully in 36-40 hours. A 40-50 cm, 1.4-2.3 kg female yields up to 140,000 eggs in a single spawning. At 19-20ºC hatching commences 42 hours after fertilization, at 20-21ºC, 38 hours, and at 23-24ºC, 29 hours. The fry can be kept in 1-ton plastic tanks and fed with oyster trocophore larvae in algae-ladened water between the third and sixth days after hatching. Beginning from the fifth day after hatching rotifers are given to larvae, and copepods are added to the diet starting from the thirteenth day.

GROWTH:

Fry of 3-8 cm length are reared in cages and reach 180-200 g by their first winter, 600-800 g by their second, and 100-1200 g by their third. Daily food supply during the warm season must be at a high rate, 6-8% of the live weight in the first year and 4-5% in the second year.

USES:

The red sea bream bring high prices in Japan, not so much due to its gastronomic or nutritional value but because of the ancient association of the red sea bream with good fortune. It is thus traditionally served at birthday celebrations, weddings, and other such occasions.

CULTURE:

The red sea bream is a robust, voracious fish and has been held in tanks for varying periods for many years. However, many obstacles have prevented the development of culture on a large scale. Fish in captivity rapidly lose their beautiful pink spotted coloration with its blue markings, and thus their commercial value is reduced . A further drawback is that it takes 3 years to obtain individuals of saleable size, 500-1000 g. fish are moved into cages with increasing mesh size during growth. The stocking capacity increases rapidly from 1 kg/m³ for 3 g fish to 2-3 kg/m³ for 20 g fish and 4-5 kg/m³ for 200 g fish. It is necessary to clean cages frequently. They must be kept immersed at a depth where they are shaded sufficiently to produce highly colored, active fish.

REFERENCES:

Akazaki, M.1960. Growth and age of the sea bream, Chrisophrys major, caught in Wakasa Bay. Bull. Jap. Soc. Sci. Fish. 26:216-222.

Fukusho, K.M., S. Okauchi, S. Nuraini, A. Tsujigado and T. Watanabe. 1984. Food value of a rotifer Brachionus plicatilis, cultured with Tetraselmis tetrathele for larvae of red seabream Pagrus major. Bull. Jap. Soc. Sci. Fish. 50:1439-1444.

Inoue, K., K. Yamano, Y. Maeno, K. Nakajima, M. Matsuoka, Y. Wada and M. Sorimachi. 1992. Iridovirus infection of cultured red sea bream, Pagrus major. Gyobyo Kenkyu 27(1):19-27.

Woo, N.Y.S.; Chung, A.S.B.; Ng, T.B. 1991. Influence of oral administration of 3,5,3'-triiodo-L-thyronine on growth, digestion, food conversion and metabolism in the underyearling red sea bream, Chrysophrys major (Temminck & Schlegel). Journal of Fish Biology 39:459-468.