Protect fish pond from stock loss during monsoon: Expert

Ludhiana, July 28

Management of fish ponds during monsoon mainly involves water management skills. Hence, farmers need to manage their ponds smartly to avert any unforeseen damage due to heavy rains.

Dr Meera D Ansal, head, Department of Aquacuture, College of Fisheries, Guru Angad Dev Veterinary and Animal Sciences University, said firstly, farmers should assure that pond dykes were strong enough to withstand erosion during rains and this could be achieved by planting grass on the dykes. Erosion adds muddiness to water, affecting its productivity due to reduced sunlight penetration leading to oxygen depletion.

In case water becomes muddy, application of limestone in accordance to water pH is recommended. Secondly, 1 to 1½ feet free board over water surface is required to accommodate the rainwater, while an automatic overflow pipe may also be provided for maintaining desired water level during rainfall, but it is to be fixed with a mesh cover to prevent fish loss. Net fencing can also be provided to prevent escape of fish with overflow in case of high intensity rainfall. The third important thing is to keep the dykes three-four ft raised above the ground level so that water from the catchment area does not enter the pond. It may bring lot of organic load and pesticides from the adjoining agricultural fields and pollute the water, which will affect survival and growth of fish, besides posing serious food safety concerns.

Dr Meera said it was vital to ensure that pH of water did not fall below 7.0 due to rainfall, which would be detrimental for fish growth. To prevent any such condition, it is advised to sprinkle limestone on the dykes (@ 10 kg/100m2) so that it mixes with the rainwater and neutralises its acidic effects while entering into the pond.

As most of the species breed during the monsoon, it is recommended that ponds should not be filled with canal water during the season. In case it is the only source of water, farmers need to fix a fine mesh net on the mouth of the inlet pipe to prevent entry of eggs and larvae of unwanted fish species (weed and predatory) along with canal water. — TNS