Common shrimp

Systematic position: The common shrimp (Crangon vulgaris) belongs to the phylum Arthropoda, class Malacostraca, order Decapoda, and family Crangonidae. While primarily known as a marine organism, in the context of coastal agriculture and mariculture, it acts as a pest capable of causing significant damage to algae plantations and juvenile aquatic plants in tidal zones.

Crops damaged: The species poses a significant threat to marine algae plantations and coastal crops adapted to brackish water conditions. The shrimp feed on delicate plant tissues, causing physical destruction of the biomass and reducing the overall quality and survival rate of the cultivated plants.

Biology and life cycle: The life cycle of Crangon vulgaris involves several larval stages within the water column. Adults are primarily benthic, utilizing cryptic coloration to camouflage against the substrate. Reproduction occurs throughout the warmer seasons, with females carrying eggs on their pleopods, which ensures high reproductive potential and rapid population growth in favorable environmental conditions.

Character of damage and harm: The primary harm is inflicted through mechanical feeding, where the shrimp use their appendages to graze on young plant shoots. This grazing activity leads to stunted growth and creates entry points for secondary bacterial and fungal infections. In areas with high population density, these crustaceans can cause devastating losses to young seedlings.

Control measures: Protecting crops from the common shrimp requires a combination of physical barriers and ecological management. Recommended strategies include:

• Deployment of fine-mesh barriers around cultivation sites.
• Management of water circulation and tidal flow.
• Regular monitoring of population density during breeding peaks.
• Implementation of non-toxic repellents to restrict access to valuable crop areas.