Fish Farming - Striped Sea Bass
Sea striped bass - Morone saxatilis (Walbaum) - a valuable euryhaline commercial fish, brought to the south of Russia and Ukraine from the USA in the 60-70s. for the purpose of acclimatization in the Azov-Black Sea basin as an object of intensive cultivation. It has excellent taste. It is necessary to become more familiar with striped bass and how they are bred and raised in aquaculture.
Content
- Where do striped bass live?
- What does a striped bass look like?
- Striped Bass Spawning
- What does striped bass eat?
- How fast does striped bass grow?
- Acclimation of striped bass
- Breeding striped bass in captivity
- Reproduction of sea striped bass in pools
- Striped Bass Stocking Density
- Growing Striped Bass
- Advantages and Disadvantages of Raising Striped Bass
Where do striped bass live?
Striped bass are widespread along the Atlantic coast of the United States and migrate along the coast. This is their historical habitat, which is why they are also called Atlantic striped bass. At the end of the 19th century. it was able to acclimatize in the waters of California, from where it spread along the Pacific coast of the United States. Perch lives in coastal waters, bays, lagoons and lower reaches of rivers. Subsequently, in 1965, it was released in the Caspian Sea and the Azov-Black Sea basin and currently the sea striped bass can be found off the coast of Russia, Ukraine and Bulgaria. This proves that sea striped bass can be grown in the Black Sea. It was also imported to Latvia, Iran and Turkey for breeding.
What does a striped bass look like?
The striped bass has a streamlined, silvery body marked by longitudinal dark stripes running from the gills to the base of the tail.
Striped Bass Spawning
Males become sexually mature at 2-3 years, females at 4-5 years. During the pre-spawning period, spawners migrate from sea and brackish waters to fresh waters, where females spawn from 0.5 to 5 million eggs. Striped bass spawn at water temperatures between 12 and 23°C. Spawning occurs in fresh water - rivers, lakes and reservoirs.
Eggs and larvae can develop normally in water with a salinity of 12-16%. Fingerlings, juveniles and adult fish live at temperatures from 6 to 30°C, with water salinity up to 35%.
Striped bass eggs are buoyant. The larvae hatch after two days.
What does striped bass eat?
What to feed striped bass? On the eighth-ninth day, the larvae begin to feed on copepod nauplii, after a few more days they willingly eat rotifers, cladocerans and copepods, then chironomid larvae, mysids and other nektobenthic and benthic organisms appear in the diet of sea striped bass. Two-month-old fry grow up to 4-5 cm. Juveniles with a length of more than 11 cm feed on fish.
How fast does striped bass grow?
Striped bass grow quickly. In the Azov-Black Sea basin, the weight of two-year-olds is 0.5 -.75; three-year-olds -1.5-2; four-year-olds - more than 2 kg. In their homeland, individual specimens of striped bass grow up to 1.8 meters. Females can weigh more than 50 kg, males - 18 kg.
Acclimation of striped bass
In 1965, several batches of young-of-the-year striped bass were released into the Azov, Black and Caspian Seas, and in 1968 they began to be raised in the ponds of the Goryachiy Klyuch fish hatchery. Somewhat later, fish breeding scientists in our country developed a technology for producing offspring of this species (Temryuk fish hatchery in the Krasnodar Territory).
Breeding striped bass in captivity
For this purpose, we used five-year-old females with an average weight of 2.1-2.8, males - 2.0-2.1 kg at a water temperature of 18-20°C. A stepwise injection of acetonated carp pituitary gland was used, a total of 5.2-6 mg per 1 kg of body weight, with the first injection containing 1/3-1/4 of this amount. The interval between injections is 26 hours. At a temperature of 19.2-19.8°C, maturation occurs in 39-49 hours. In fish that have matured for the first time, the absolute fecundity is 263-486, the working fecundity is 114-149 thousand eggs.
Males were injected with a suspension of the pituitary gland at the rate of 1-2 g per 1 kg of body weight, sperm was obtained after 18-23 hours. A single volume of ejaculate was 16-3 7 ml.
The fertilized eggs are placed in Weiss devices. There is a high sensitivity to increased water flow at 19°C after 37-39 hours of incubation; The recommended mode is about 1 l/min.
Hatching of the larvae occurs after 48-50 hours, the survival rate of prelarvae from eggs is about 24%, which is probably due to the imperfection of the incubation apparatus.
The length of the prelarva is 2.5-3.2 mm, the average weight is 1.2 mg. After 5 days, in larvae with a length of 6.2 mm, the swim bladder begins to fill with air. At this time, live food is added to the mesh gas cages where the larvae are located - rotifers and small cladoceran crustaceans at the rate of 50-70 specimens. Is it on fixing Dimensions of food at the age of larvae 5-8 days - 170-220 microns; 9-14 days - 250-700; 15-30 days - 800-1000 microns. After 30 days, with a weight of 115 mg and a length of about 20 mm, the larvae are transplanted into ponds. Over 150 days of pond rearing, the average weight of fingerlings was 11.3 g, survival rate was 80%.
Reproduction of sea striped bass in pools
Fertilized eggs can also be obtained as a result of spawning of injected spawners in plastic or concrete round pools. This method of breeding sea striped bass is interesting because 100% of the producers remain alive, the fertilization of eggs is very high and reaches 80-90%, 200,000 larvae can be obtained from each female.
With this method, females are selected with oocytes with a diameter of at least 950-1000 microns and injected with the pituitary gland of the carp in two doses. After stimulation, 2-3 breeding males are added to each female. Spawning occurs after 2 days. Fish spawn in the pool at a temperature of 17-19 C. 3-4 hours after spawning, eggs are caught from the pool with gauze nets and placed for further incubation in Weiss apparatus, 150-200 thousand pieces each. to the device. The water temperature during incubation should not exceed 22 C, otherwise the eggs will die. The duration of the incubation period depends on the temperature and varies from 34 to 44 hours. The prelarvae are kept in trays without flow for 2-3 days, the stocking density is 50 thousand pcs/m3. Yolk resorption in striped bass larvae at a temperature of 20-22 C is completed on the 5-6th day, the swim bladder is filled with air on the 4th, 5-6th day, the larvae switch to active feeding at the age of 4-5 days, when they feed Artemia salina nauplii are introduced, and zooplankton is introduced 10 days after hatching.
The resulting juvenile striped bass are raised in ponds with an area of 0.05 hectares and fed with minced fresh low-value fish. With this intensive method of growing striped bass in ponds, fingerlings reach a weight of 30-60 g, two-year-olds - 500-1000, three-year-olds - 800-1500, four-years - 1000-2000, five-years - 2000-3500, six-years - 3500-6000 g. Fish survival weighing more than 25-30 g is close to 100%.
Striped Bass Stocking Density
Juveniles are released into ponds on the 13-15th day with a stocking density of up to 100 thousand pieces/ha, thinning and sorting gradually gradually reducing the stocking density to 30 thousand pieces/ha.
Growing Striped Bass
When growing sea striped bass in a polyculture with carp and herbivorous two-year-old striped bass with an initial weight of 30 and three-year-olds - 291 g with a total stocking density of 3510 specimens/ha, 2090 kg/ha were obtained, including 1423 kg/ha of striped bass with an average weight 537 and 1138 g each and 667 kg/ha of carp and herbivorous fish with an average weight of 680-790 g.
When growing striped bass in ponds, the weight of two-year-olds reaches 0.5, three-year-olds - 1.0-1.5, four-year-olds - 2.0-2.5, five-years - 3.0-3.5, six-years - 3.5- 6.0 kg.
When transported in plastic bags with oxygen, the stocking density of fry with an average weight of 3-6 g is 200 specimens. for 1 package, fingerlings with an average weight of 30-40 g - 20-40 pcs. per package.
Advantages and Disadvantages of Raising Striped Bass
What benefits does a fish farmer get when raising striped bass?
- Striped bass is a promising object for grazing aquaculture in natural and artificial reservoirs for complex purposes, both in fresh and salt water.
- Striped bass are grown in polyculture as a supplemental fish in fish ponds.
- It has valuable meat suitable for making balyk products.
- It is possible to grow striped bass in sea cages.
- Sea striped bass is recommended for cultivation only in cages, but also in fenced off areas of the sea or estuary in the Azov-Black Sea basin and the Mediterranean Sea.
- Can be grown in ponds as a sport fishery.