6 Tips for shrimp farmers during the rainy season
The rainy season poses a challenge for shrimp farmers in Indonesia as almost all ponds are outdoors, making them vulnerable to environmental changes. If farmers do not take preventive action regarding changes in the environment, it will certainly have an effect on shrimp that are susceptible to disease. The following things must be considered during the rainy season:
1. Changes in temperature, pH, and oxygen.
Rain can cause pond water temperatures to drop by 2-3°C. Low water temperature can reduce the metabolic rate of shrimp. Shrimp activity becomes slower, moves less, and tends to gather at the bottom of the pond. The pH of rain is usually around pH 6.5-7.0. Rain will directly reduce the pH of pool/pond water by 0.3-1.5 in a short time. A drop in pH can cause shrimp to become stressed and susceptible to disease. Even though dissolved oxygen in water increases when the temperature drops, it turns out it is not comparable to the decrease in oxygen due to reduced phytoplankton (dead) and increased heterotrophic bacteria caused by increased organic matter from plankton crashes. This condition also allows the emergence of compounds such as sulfide acid which is very toxic to humans. Low pH and the appearance of pathogenic bacteria.
2. Changes in salinity and alkalinity.
The influence of rainwater dilutes pond water so that the salinity and alkalinity values decrease. When salinity drops very quickly, the shrimp will experience a molting process but limited minerals cause the shell to harden more than normal. This is very susceptible to cannibalism and disease infections that cause death.
3. Plankton population and accumulation of organic matter.
Phytoplankton die due to changes in water quality parameters and limited sunlight so that oxygen levels fall. Most of the dead phytoplankton (90%) will accumulate at the bottom of the pond as organic material. During the rain, shrimp do not eat normally, if they continue to be fed, overfeeding will occur. The slow decomposition process by bacteria will cause the accumulation of excess organic material at the bottom of the pond.
4. Decreased shrimp immunity level.
Changes in several water parameters such as temperature, pH, oxygen, salinity, alkalinity, and organic matter can result in an unstable ecosystem for shrimp growth. Apart from that, this condition also results in stress levels and a decrease in shrimp immunity against disease infections.
Recommended actions/tips based on the problems above are:
author : Jery Prastiyo