New technique for integrated fish-duck farming: what size of fry should be stocked, and what are the benefits

Small-sized fingerlings can be caught and eaten by ducks. Therefore, fry of 50 g or more must be stocked in the pond to solve this problem.

 1. Integrated fish-duck farming. That is, build a duck house on the pond embankment, fence off part of the embankment as an activity area, and raise the ducks directly on the fish pond. This method can give relatively good play to the ecological effect of fish-duck symbiosis and mutual benefit. Farmers who choose a suitable management method according to local conditions can achieve the greatest benefits.

 2. Make a reasonable combination. For duck raising in fish ponds, generally 100-150 ducks per 667 sq m is appropriate. If more than 200 ducks are raised, the main species should be filter-feeding and omnivorous fish such as silver carp, bighead carp, tilapia, or common carp and crucian carp, and it is not suitable to mainly raise grass carp, bream, or black carp. In addition, attention must be paid to changing the water and increasing oxygen. Duck raising in a fish pond should not exceed 250 ducks per 667 sq m, otherwise fish yield will decline noticeably. Calculating at 40-50 kg of manure per duck per year, a duck-raising fish pond will add 4800-7500 kg of fertilizer per 667 sq m compared with a pond without ducks, effectively fertilizing the pond water, breeding large amounts of plankton, and providing sufficient feed for the growth of silver carp and bighead carp. A duck-raising fish pond can be mainly stocked with silver carp and bighead carp, with 50-75 kg, or 1000-1500 fish, of fingerlings per 667 sq m. If mainly raising grass carp and black carp, stock 75-1500 kg, or 1000-1500 fish, of fingerlings per 6667 sq m. With proper raising, 667 sq m can achieve a net fish yield of more than 400 kg.

 3. Strengthen feeding management. To make it easier to manage the duck flock in a centralized way, old netting, screen cloth, and similar materials can be used to enclose part of the fish pond as a duck activity pool, preferably raising 2-4 ducks per sq m of water surface, with the netting extending 40-50 cm above and below the water surface so that fish can enter and leave freely. Feed the ducks at the embankment activity area every morning and evening. In the evening, after the ducks enter the house, sweep the duck manure and leftover feed from the area into the pond. In the morning, drive the ducks out of the house, and after collecting the eggs, sweep the duck manure inside the house and pen into the pond. In summer, the duck flock produces a large amount of manure and the water becomes too fertile, so new water should be added in time and the amount of fertilization reduced.

 Summary: Although integrated farming with fish can reduce costs, when raising ducks in a fish pond, the water quality issue must be paid attention to. When ducks move on the water surface, they inevitably produce duck manure, and if the fish pond water is not changed to a certain extent, it can easily cause the fish in the pond to develop diseases because the water quality is not clean.

Harmful organisms such as diseased fish and the larvae of aquatic insects, eliminating the adverse effects on fish growth. At the same time, when duck manure falls into the water, a small part is directly eaten by fish in the form of organic detritus, while most is decomposed in free form and absorbed by the water body, promoting plankton growth and increasing the natural food of fish, thereby increasing the yield of fertilized-water fish. In addition, the duck flock swimming back and forth on the water surface increases the dissolved oxygen density in the water to a certain extent and improves the water environment; integrated fish-duck farming solves problems such as environmental pollution caused by duck manure.