American red fish

Breed name: American red fish

English name: redfish

Common name: red fish, red fish, spotted tail fish, sea bass

Scientific name: Sciaenopsocellatus

Biological characteristics

(1) morphological characteristics.

The American red fish is hammer-shaped, flattened on the side, with a slightly raised back and the highest at the starting point of the dorsal fin. The head is medium-sized, the mouth fissure is large, showing the end position, and the teeth are small, closely arranged and sharp. Two pairs of nostrils, the latter one is oval, slightly larger. The superior lateral position of the eye, the posterior edge and the end of the cleft mouth are flat and medium size, distributed on both sides of the head. The posterior edge of the anterior operculum is serrated and there are two sharp-toothed protuberances on the edge of the posterior operculum. The ladder scale, the lateral line is obvious, the back is light black, the scale has silver luster, the middle part of the abdomen is white, both sides are pink, the caudal fin is black, and there is a black spot above the most obvious caudal lateral line. The total length is 2.65-2.7 times of body height.

(2) Life habits

Red fish like to cluster, swim quickly and have obvious migratory habits. it is a wide temperature and salinity fish with an optimum temperature of 10-30 ℃ and an optimum temperature of 18-25 ℃. However, it has been reported that it can withstand a low temperature of 2 ℃, has a wide range of salinity, and can grow and develop normally in fresh water, brackish water and sea water. Red fish is a fleshy omnivorous fish with a high food chain. It mainly feeds on shellfish, cephalopods and small fish in natural waters. The artificial compound food is also eaten under the condition of artificial feeding. The growth rate of red fish is fast. In the country of origin, the individual in that year can reach 50-1000 grams, and the largest individual can reach 3000 grams. Under the condition of artificial culture, it can reach 1000 grams in the first anniversary of farming in Taiwan. Qingdao and Lianyungang area can reach more than 500 grams in one year.

(3) breeding habits

The males of red fish can be sexually mature at 4 years old and the females are more than 5 years old. Generally, the parent fish for artificial reproduction should choose more than 4-year-old males and more than 5-year-old females, so that a large number of eggs can be obtained and the fertilization rate is high. The number of eggs of red fish is relatively large, generally the number of eggs is 5-2 million, and more than 3 million eggs are spawned in batches. It can oviposit continuously for a period of time, and it is a floating egg with a diameter of 0.9-1.0mm. Under the condition of 23-25 ℃, the membrane can be broken in about 24 hours and grow nutritionally by yolk within 3 days of hatching.

Economic character

The growth rate of American red fish is fast, the culture yield is high, and the market price is good. Generally in Qingdao and Lianyungang area, 500-750g adult fish can be cultivated in that year, and the highest yield per mu is 1600 kg. The price is 60 yuan / 500g in the domestic market. Artificially cultured American red fish has many advantages, such as suitable temperature, wide salt range, strong tolerance to hypoxia, wide source of feed, mature breeding technology and so on, so it is worth popularizing and producing locally.

Aquaculture status

The juvenile American red fish 8mm was first introduced from the United States by the first Institute of Oceanography of the State Oceanic Administration in 1991. It was cultivated in laboratory for one year, and the average weight gain of each fish was 400g. During the three years from 1992 to 1995, the average annual weight gain of each tail was 1000g. Adult fish have been spawning since 1995. Pond culture began in 1996. At present, American red fish has been widely promoted to the coastal provinces and cities of our country. In 1997, Gaogongdao Township of our city introduced 2000 seedlings from Qingdao for shrimp pond and cage culture with good results. American red fish culture has higher economic benefits.