Methods and techniques for stocking fish fingerlings in early spring

Early spring is the best season for stocking fish fingerlings, because during this period the water temperature is relatively low, the fish's activity is reduced, and the fish scales are tight, the fish body is firm, and they are not easily injured during netting, catching and transport, which can increase the survival rate of stocked fingerlings. When stocking fingerlings, attention should be paid to the following aspects:

Fingerling quality

Fingerlings of the same species and same age should be uniform in size, with little difference in body length and weight, thick back muscles, bright coloration, scales and fins intact without damage, swimming actively and normally, strong upstream-swimming ability, and after being taken out of the water and placed in a basin, the gill covers do not open, the tail does not bend, they jump continuously, and there are no wounds or parasites on the body surface.

Fingerling disinfection

1. The medicine should be prepared and used immediately; clean water should be used to prepare the solution, and fertilized water should be avoided; direct sunlight should be avoided when soaking and washing the fingerlings with the medicine. 2. The dosage must be accurate, avoiding insufficient dosage or overdose. 3. The soaking time should be appropriate. If the fingerlings are found to be unable to endure it, water should be added immediately or the fingerlings should be placed into another container.

Stocking method and time

Before the fingerlings are put into the pond, first check whether the effectiveness of the pond-clearing medicine has worn off. The method is: place a small cage net in the pond where the fingerlings are about to be stocked, put a few dozen test fish inside, observe them overnight, and see whether their activity is abnormal. If symptoms such as restlessness, struggling at the surface, and swimming about in all directions appear, it means there is still residue of the pond-clearing medicine, and the fingerlings must not be stocked immediately; only after the medicine has completely disappeared can the fish be released. In addition, before the fingerlings are put into the pond, the whole pond must also be seined 1-2 times with a fine-mesh net to thoroughly remove harmful insects, frog eggs, wild miscellaneous fish and other organisms in the pond that may harm the fingerlings, ensuring the safety of the fingerlings after stocking.

It is best to choose noon on consecutive sunny days for stocking, as fingerlings adapt fastest at this time and the survival rate is also the highest. In windy weather, fingerlings should be released at the upwind area of the fish pond, so as to avoid being blown to the pond edge and killed when stocked at the downwind area.

Pay attention to the temperature difference when stocking. When stocking, note that the temperature difference between the water in the container holding the fingerlings and the pond water must not exceed 3°C. If the temperature difference is too great, the water temperature in the container should be adjusted to bring it close to the pond water temperature. For fingerlings transported in oxygen-filled plastic bags, a "seedling acclimation" process is needed when stocking. When the fingerlings are put into the pond, they should also be counted accurately.