Hatching Hapas for Fishes
- Double cloth hatching hapas are most extensively used.
- The hapa is fixed in the water with the help of bamboo poles in shallow waters.
- This hapa is double walled, with an outer wall made of either thin or coarse muslin cloth and an inner wall made of round mesh mosquito netting cloth.
- The most frequently used cloth for a hatching hapa is 2 x 1 x 1 m in size for the outer one and the inner wall size is 1.75 x 0.75 x 0.9 m.
- The water depth is maintained around 30 cm.
- The hapas are arranged in a series. 75,000-1, 00,000 eggs are kept in one hapa inside the inner wall for hatching.
- After hatching, the hatchlings enter into outer hapa through the mosquito netting cloth leaving the egg shells, spoiled eggs and the dead eggs.
- After hatching, the inner hapa is removed.
- The hatchlings in the outer hapa are kept for a period of 40 hours till the yolk sac is absorbed. The percentage of hatching is 40- 50%.
- The main advantages are that the cost is very less and the eggs are away from earth which will not pollute and cause mortality.
- The disadvantages are the pores of hapa get clogged due to silt deposition which causes heavy mortality, they have a short life period of about 2 years. Weather fluctuations result in mortality and they need more water.
- Garfil hatching hapas can also be used in place of cloth hapas. The design, construction and arrangement are similar to cloth hapas.
Submitted by naipagropediaraichur on Tue, 18/12/2012 - 15:27