FISH FARMERS NEED TO BE ALERT DURING SUMMER SEASON

FISH FARMERS NEED TO BE ALERT DURING SUMMER SEASON

13-AUG-ENG 2

RAJIV NAYAN AGRAWAL

SASARAM----------------------Dr. Pragya Mehta, Assistant Professor working in the Department of Fisheries of Narayan Krishi Vigyan Sansthan, operated under Gopal Narayan Singh University, Jamuhar, says that if management is done in scientific ways, then good production can be obtained from fish farming even in summer season. Summer season is very challenging for fish farmers because during this time the temperature of water increases more than normal. Due to this, the amount of dissolved oxygen in water decreases and it has a negative effect on the health and production of fish. According to Dr. Mehta, for scientific management, the depth of the pond should be at least 5–6 feet so that the coolness remains in the lower layer. The presence of trees giving shade on the banks of the pond helps in reducing the effect of heat. When the water level in the pond decreases, water should be supplied from an external source from time to time. Especially in the morning, the amount of dissolved oxygen becomes very low, due to which the fish have difficulty in breathing. In such a situation, equipment like aerator or paddle wheel should be used before sunrise and after sunset. If equipment is not available, oxygen can be supplied by stirring the water or by creating a flow of fresh water. If the fish come to the surface and start breathing through the mouth, then the use of feed and fertilizers should be stopped immediately and the process of aeration should be started. In summer, the appetite of fish generally decreases, so they should be given a balanced diet containing 25% protein in the amount of 1.5–2% according to their body weight before 9 am or after 4 pm. To prevent wastage of feed, it is beneficial to adopt bag feeding method. In case of any abnormal behavior, feeding should be stopped immediately. The presence of planktons in the pond acts as a natural diet for the fish. For this, use organic manure (such as rotten dung, biogas slurry, vermicompost) and inorganic fertilizers (such as urea, super phosphate) in a balanced manner. Use of fertilizers in large quantities can promote excessive growth of algae, which can lead to oxygen deficiency at night. If the water colour becomes excessively green, brown or red, stop using fertilizers immediately and as per requirement clean the algae, scrape the water and use alum or gypsum. Fishes become more susceptible to diseases during summer season, so regular monitoring of their activities and appearance is necessary. Use lime, potassium permanganate or cefax carefully to prevent diseases. In case of crisis, when the fishes start coming to the surface, immediately use oxygen tablets or sprinkle water and keep the aerator running as a backup. Oxygen tablets prove to be very useful especially in small ponds. Under water management, the nutrient water of the pond should be used for irrigating the fields and in return fresh water should be put into the pond so that the quality of water is maintained and the crops also get nutrition. By doing so the need for chemical fertilizers is reduced. Thus if fish farming is done with a scientific approach then it can be made safe, sustainable and profitable even in the summer season.