Crayfish, commonly referred to as crawfish, have become a focus of artificial breeding due to the depletion of natural resources, supply shortages, and rising market prices. To address these challenges, the author implemented a co-cultivation model involving crayfish and crustaceans in the same pond, achieving impressive results that are worth promoting and applying. Below is a detailed introduction of the technology:
The pond setup requires a quiet location with convenient transportation, reliable water supply, good water retention, and fertile soil, ideally clay or loam. The water must be clean and free from pollution. Pond sizes can vary between 5 to 15 acres, with a water depth of 0.8 to 1.2 meters and a slope ratio of 1:2 to 1:3. A 60 cm high plastic or aluminum barrier is installed around the pond to prevent escape. Bamboo and wooden stakes serve as support structures. Water inlet and outlet pipes, approximately 40 cm in diameter, are placed in opposite corners, covered with fine mesh or barbed wire to prevent crabs and crayfish from escaping. After harvesting, the pond is cleaned, and 50 kg of tea seed cake and 100 kg of quicklime per acre are applied for disinfection, which effectively eliminates predators without harming the crayfish in their burrows.
Aquatic plants and snails play a crucial role in successful breeding. Waterweeds and snails provide high-quality food for both crabs and crayfish, help purify the water, and offer shelter from predators. They also provide shade during hot summer months, helping to lower water temperature. Aquaponic zones are established around the pond, with bamboo poles and ropes used to fix water plants every 5 meters. Before the Qingming Festival, 300 to 500 kg of live snails per mu are introduced to breed naturally, serving as a food source for the aquatic species.
Crab seedlings are purchased and raised in a net-fenced area that occupies 5% to 10% of the total pond area. After about one month of growth, when they reach around 6,000 per kilogram, they are moved into the main pond. Crabs from the Yangtze River system are preferred, ideally raised in simulated natural soil pools. The stocking density is about 160,000 per kilogram. After desalination for over 7 days, the salinity should be below 3‰ before release. Healthy seedlings with uniform size, pale color, and active movement are selected, transported in air-conditioned vehicles.
Once transported to the pond, the crab seedlings are acclimated by submerging their containers in the pond water for 1–2 minutes, repeated 2–3 times. After being released, they are fed egg yolk initially, every 2–3 hours. As they grow into juvenile crabs, they are transitioned to fish cakes, bean cakes, and bran, along with specialized bait. Feeding rates gradually decrease from 100% to 5–7%.
For shrimp seedlings, two stocking methods are used: spring stocking of larvae and autumn stocking of mature shrimp. In spring, larvae are stocked and grown for 2–5 months, reaching sizes of 2–4 cm. In autumn, mature broodstock (40 grams or more) are stocked at a 3:1 male-to-female ratio. From April to May, land cages are used to catch broodstock, allowing self-reproduction within the pond. Shrimp stocking density is generally around 5,000 per acre.
In addition to natural food sources, feeding begins in April, with plant-based foods like water grass, wheat, corn, and bean cakes, along with snails, oysters, and clams. Fixed feeding schedules and appropriate spraying ensure all animals get enough food. From August to September, plant-based feeds dominate, while animal-based feeds are emphasized from October to December. Water is changed every 10 days during hot seasons, with 1/3 of the water replaced each time. Daily inspections in the morning and evening are conducted to monitor water quality, feeding conditions, aquatic vegetation, and anti-predator facilities. Weather conditions are closely watched to prevent escapes, especially from rats, frogs, and birds. Lime water is sprayed every 15–20 days, using 5 kg of quicklime per acre.
Harvesting typically occurs from February to March of the following year. Crabs are captured using dip nets, and once most are collected, the pond is drained. Water peanuts are spread on the pond edge, and after releasing the water in the evening, crabs gather under them, allowing for efficient collection. Krill crayfish are harvested regularly throughout the year using ground cage nets. This method ensures high efficiency and sustainability in aquaculture practices.
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