Spotted Locust Infestation in Idukki, Kerala

Context: Farmers in Idukki, Kerala, are facing an agricultural crisis due to an infestation of spotted locusts.

Key Characteristics:

• Defense Mechanism:
  Spotted locusts possess bright warning colors to deter predators. They also eject toxic foam as a defense mechanism and can produce a sharp rasping sound for additional protection.
• Movement:
  These locusts have slow movement, which makes them relatively easy to catch. They typically jump low and do not fly extensively.

Causes of Locust Swarming:

• Gregarisation:
  Locusts shift into a gregarious phase due to environmental triggers like excessive rainfall, flooding, and irrigation in cereal crops.
• High Rainfall:
  Increases lush foliage, leading to higher nymph populations and encouraging them to gather together.
• Flooding:
  Expands breeding grounds by creating moist conditions conducive to egg-laying.
• Temperature:
  Lower temperatures enhance nutrient absorption and slow down growth, extending the locust lifecycle.
• Soil Moisture:
  Post-flooding, wet soil enables continuous egg-laying even during dry spells, sustaining the locust population.
• Serotonin Surge:
  When locusts sense the presence of other locusts through sight, smell, or touch, serotonin levels rise, activating the genes responsible for gregarious behavior.
• Hopper Contact:
  Physical contact between hoppers (young locusts) leads to gregarisation, prompting mass movement in search of food, causing severe crop damage.