Grass shrimp

Taxonomic position: Palaemonetes pugio belongs to the order Decapoda, family Palaemonidae. While naturally occurring in estuarine habitats, it acts as an opportunistic pest in controlled agricultural aquatic environments where it interacts with cultivated plant species.

Affected crops: This species primarily impacts aquatic crops such as rice in saline-influenced paddies and various seaweed or aquatic plant nurseries. In these environments, they consume delicate tissues, causing significant economic loss to producers.

Biology and life cycle: The lifecycle involves multiple larval stages dependent on water salinity and temperature. Populations often peak during warmer months, leading to high grazing pressure on surrounding vegetation, which the shrimp utilize for both shelter and direct nutrition.

Damage and pest status: The primary harm is caused by the physical feeding activity of the shrimp on emerging sprouts. By consuming young leaves and stems, they severely limit the photosynthetic capacity of the plants, leading to stunted growth, patchy crop stands, and increased susceptibility to secondary infections.

• Regular monitoring of population densities within irrigation channels.
• Installation of fine-mesh screening systems to prevent entry into growing areas.
• Introduction of biological control agents like predatory fish species.
• Manipulation of salinity levels within management protocols to discourage shrimp survival.