AQUACULTURE MANAGEMENT: SOLUTIONS FOR SEASONAL CLIMATE CHANGE ADAPTATION

Climate change and seasonal weather variations are becoming major challenges for the aquaculture industry. Unpredictable temperature fluctuations, prolonged heavy rains, droughts, and severe storms directly affect water quality, aquatic animal health, and production efficiency. Therefore, proactively managing ponds and applying seasonal adaptation strategies are essential for reducing risks, improving productivity, and ensuring sustainable aquaculture development.

1. Effects of Temperature Fluctuations on Aquaculture

Cold Season: Reduced Feeding and Slower Growth

When water temperatures drop, the metabolic processes of fish and shrimp slow down. This results in reduced feed intake, slower growth, and weakened immunity.

During prolonged cold conditions, especially in areas experiencing sudden temperature drops, dissolved oxygen levels may decrease significantly, causing oxygen deficiency and increasing mortality rates.

Cold Season Management Solutions

• Reduce feed amounts according to the actual feeding behavior of fish

• Monitor water temperature daily

• Maintain stable pond water levels to minimize temperature fluctuations

• Use paddle wheels or aeration systems to increase dissolved oxygen

• Supplement vitamins and minerals to improve immunity

Hot Season: Risk of Heat Stress and Oxygen Depletion

High temperatures increase the oxygen demand of fish rapidly. However, warm water contains less dissolved oxygen, creating an imbalance that may lead to fish gasping at the surface, heat stress, or mass mortality.

In addition, hot weather promotes excessive algae growth, increasing the risk of algal blooms and sudden pH fluctuations.

Hot Season Management Solutions

• Increase aeration at night and early morning

• Feed during cooler times of the day

• Reduce feed amounts when fish show signs of stress

• Regularly monitor dissolved oxygen, pH, and temperature

• Avoid overfeeding to prevent water pollution

2. Rainfall Variations and Their Impact on Aquaculture Ponds

Rainy Season: Declining Water Quality

Prolonged heavy rainfall can suddenly alter water parameters such as pH, salinity, alkalinity, and temperature. In addition, rainwater runoff may carry:

• Mud and sediment

• Organic matter

• Agricultural chemicals

• Pathogens

These factors destabilize the pond environment, making fish more vulnerable to stress and disease outbreaks.

Rainy Season Management Solutions

• Reinforce pond dikes and drainage systems

• Protect areas vulnerable to overflow

• Check pH levels after heavy rain

• Use probiotics or biological products to stabilize water quality

• Replace water when necessary

Dry Season: Risk of Drought and Algal Blooms

During the dry season, reduced water volume increases stocking density. Organic waste, toxic gases, and nutrients become more concentrated, creating favorable conditions for excessive algae growth.

If not properly controlled, algal blooms can reduce dissolved oxygen levels and release toxins harmful to aquatic animals.

Dry Season Management Solutions

• Maintain appropriate pond water levels

• Regularly siphon pond bottoms to remove waste

• Control feeding rates

• Increase oxygen levels using aerators

• Monitor algae density and parameters such as NH3 and NO2

3. Impacts of Strong Winds, Storms, and Cloud Cover

Extreme weather events such as storms, tropical depressions, or strong winds may cause:

• Large waves damaging pond embankments

• Power outages affecting aeration systems

• Water stratification leading to oxygen depletion at the pond bottom

• Stress in fish caused by sudden environmental changes

Extended cloud cover can also reduce algae photosynthesis, lowering dissolved oxygen levels in the water.

Preventive Measures

• Prepare backup generators

• Reinforce pond embankments and aeration systems

• Reduce feeding before storms or heavy rains

• Continuously monitor dissolved oxygen levels

• Harvest early if severe weather conditions are expected

Important Principles to Reduce Seasonal Stress in Fish

Most seasonal weather changes cause stress in aquatic animals. When fish or shrimp are stressed, their immune systems weaken, increasing the risk of disease outbreaks. Therefore, farmers should minimize all possible stress factors.

Key Management Principles

Reduce Feed Amounts

When fish reduce feeding activity, feed rations should be adjusted to avoid waste and reduce metabolic pressure.

Limit Handling and Transportation

Harvesting or transporting fish during unfavorable weather conditions may cause shock and increase mortality.

Reduce Stocking Density

Overcrowding accelerates oxygen depletion and increases disease transmission.

Regularly Monitor Water Quality

Important parameters to monitor include:

• Dissolved oxygen (DO)

• pH

• Temperature

• Alkalinity

• NH3 and NO2

• Salinity

Managing aquaculture under seasonal climate fluctuations requires farmers to closely monitor environmental conditions and adjust farming techniques accordingly. Controlling temperature, rainfall, dissolved oxygen, and water quality not only reduces stress in aquatic animals but also minimizes disease risks, improves productivity, and maximizes economic efficiency.

As climate change becomes increasingly complex, applying flexible and sustainable management solutions will be the key to maintaining stable and successful aquaculture production in the future.