A Detailed Guide to the Latest Scientific Farming Techniques for Paddlefish

Paddlefish is one of the fastest-growing freshwater fish species; paddlefish grow quickly and adapt strongly to their environment, tolerating both low and high temperatures. Join us below to learn how to raise paddlefish.

Latest Scientific Paddlefish Farming Techniques

1. Farming Location

The paddlefish farming site was chosen at the Chengqian Wodou Reservoir. The farming area has a large water surface, with a water depth of more than 6 m, dissolved oxygen of 6-9 mg/L, pH of 7-8.4, total hardness of 20-40 mg/L, ammonia nitrogen of 0.02-0.06 mg/L, and nitrite of 0.0015-0.01 mg/L. The water quality is good and meets all the requirements of GB1160 "Water Quality Standard for Fisheries" and NY5051-2001 "Water Quality for Freshwater Aquaculture Water of Pollution-Free Food".

2. Cage Setup

For paddlefish cage setup, refer to silver carp cages. Choose waters rich in plankton, with a requirement for stable water flow, shelter from wind and sun, and a quiet environment. The cage frame uses a simple moso bamboo frame. The cage body material uses knotless polyethylene netting. The cage specifications are 5 m × 5 m × 2.5 m, with a mesh size of 2.5 cm. Paddlefish are afraid of light, so the cage surface is covered with black film.

3. Seedling Selection

For paddlefish seedlings, choose high-quality seedlings with a robust physique, lively swimming, uniform size, and no disease or injury. The stocking density is 20-40 fish per sq m. The size is 10-15 cm. Because paddlefish seedlings are relatively sensitive to water temperature changes, the temperature difference when the seedlings enter the cage should not be too large, preferably not exceeding ±2℃, and should be adjusted to be as consistent as possible. Before entering the cage, disinfect the fish body with 1.5-2.0% salt water for 8-10 minutes.

4. Stocking Density

When paddlefish are raised alone, at a body length of 50-60 cm and a weight of 1 kg, stock 80-100 fish per mu; at 2-3 kg, stock 40-50 fish per mu. When polycultured, at a body length of 25 cm, stock 50-70 fish per mu, reaching 1 kg by the end of the year. At a body length of 50-60 cm, stock 20-50 fish per mu, reaching 2-3 kg by the end of the year. In the third year, stock 7-8 fish per mu. For adult fish pond culture, it is not advisable to polyculture them in small ponds or intensive high-yield ponds, because intensive ponds have high yield and high density, with dissolved oxygen fluctuating greatly, and rotational harvesting and stocking are all very unfavorable to paddlefish.

5. Scientific Feeding

In the early stage of stocking, paddlefish are mainly fed zooplankton (such as bloodworms), then gradually domesticated to switch food and instead be fed floating pellet feed, supplemented by nighttime light luring for feeding. The feed is required to be fresh and not spoiled, nutritious, and suitable in particle size. Feeding follows the "four fixed" principles. When the water temperature is 20-30℃, the daily feeding rate is 1.5-3%. When the water temperature is below 20℃, the daily feeding rate is 0.5-1.0%, adjusted in time according to feeding conditions, weather, water quality, and so on. The feeding frequency is 3 times per day, at 07:00-08:00, 11:00-12:00, and 18:00-19:00 respectively.

6. Daily Management

Paddlefish grow very quickly, so they should be cultivated by size in a timely manner to avoid polarization, which helps improve the survival rate. Strictly implement the morning, noon, and evening cage inspection system, carefully observe the feeding and activity of the paddlefish, and promptly remove residual bait. Regularly flush the cages to prevent mesh clogging from affecting water exchange inside and outside the cage. On rainy days and during storm seasons, pay attention to reinforcing the cages at any time. Also frequently check whether the cages are damaged, and repair them promptly if damage is found. Black light-shading nylon cloth and anti-theft netting should also be installed at the upper opening of the cage. Record air temperature, water temperature, feeding amount, and the number of diseased and dead fish every day. If abnormal conditions are found, take measures promptly.

7. Fish Disease Prevention and Control

For paddlefish disease prevention and control, adhere to the principle of "prevention first, health management." During seedling stocking and each sorting, bathe the fish with 1-2% salt or 0.4 mg/L dibromohydantoin and other drugs before entering the cage, and about every 20 days splash 15 mg/L quicklime and 0.3 mg/L dibromohydantoin inside the cage for disinfection. The use of prohibited drugs is strictly forbidden in the waters around the cages.

Paddlefish Living Habits

Paddlefish have strong adaptability, grow rapidly, are gentle in temperament, and have a short food chain. They are the only fish among all sturgeons that feeds on zooplankton. Their feed sources are wide, and they are easy to raise and catch, making them suitable for culture in reservoirs, lakes, ponds, and other waters. The feeding habit of paddlefish is similar to that of bighead carp; it is a filter-feeding fish that mainly feeds on zooplankton and cladocerans, especially preferring water fleas, and occasionally feeds on small aquatic insects such as chironomid larvae. Paddlefish with a body length below 12 cm can eat zooplankton one by one, and also eat small fish and small shrimp; when the body length exceeds 12 cm, their feeding organs are fully developed and they switch to filter feeding, able to capture rapidly swimming copepods.

As individual paddlefish grow, they also feed on pellet feed. In the juvenile stage, because they have a long snout and an unusual body shape, when feeding on commercial compound pellet feed, their abdomen turns upward, with a unique movement that is endearing, giving them high ornamental value, and they can be raised as a high-grade ornamental fish.

History of Paddlefish

Paddlefish scientific name: American paddlefish (also known as duckbill sturgeon). English name: Polyodonspathala. Paddlefish, scientific name "American paddlefish," is native to the Mississippi River basin in the United States. It is a large freshwater economic fish belonging to the order Acipenseriformes, family Polyodontidae. It has lived on Earth since 300 million years ago (that is, the dinosaur period) and is a rare sturgeon species that has survived, and is one of only two species in the family Polyodontidae in the world. It belongs, together with the Chinese sturgeon and the paddlefish in the Yangtze River waters, to the order Acipenseriformes, family Polyodontidae.

Characteristics of Paddlefish

Looking at its appearance, the fish mouth is flat and resembles a duck bill, yet several times longer than a duck bill. With a body more than 50 cm long, the long, flat mouth already accounts for more than half of it. The whole body is smooth, with a dark gray fish body and no scales. Tasting its flavor, the meat is very tender and extremely delicious, and it has few bones and plenty of meat, almost just a single backbone directly connected to the duck bill. The bones of paddlefish are transparent and very crisp, and can be bitten and eaten. The precious quality of paddlefish, combined with the chef's refined culinary skills, whether boiled, braised, or steamed, not only gives the fish meat a similarly tender texture and the fish bones a similarly soft and crisp quality, but is also sweet and juicy and moist to the mouth.

Paddlefish feed on zooplankton. If polycultured, they do not need to be fed feed separately. The main concern in raising paddlefish is parasitic types, so more prevention is needed.