Three-spined stickleback

Systematic position: The three-spined stickleback (Gasterosteus aculeatus) belongs to the order Gasterosteiformes and the family Gasterosteidae. While it is a natural fish species, in the context of commercial aquaculture, it is considered a pest or "weed" fish that disrupts the biological balance of managed pond systems.

Damaged cultures: The species poses a threat to intensive fish farming operations, particularly those focused on rearing carp, trout, or other commercial species. By infiltrating breeding ponds, the stickleback compromises the production environment, leading to significant economic losses for fish farmers.

Biology and life cycle: These fish are small, characterized by three sharp dorsal spines. They demonstrate sophisticated breeding behavior where the male builds a nest and guards the eggs. Their high adaptability and ability to survive in various salinity levels allow them to colonize almost any water body efficiently.

Nature of damage and harmfulness: The primary damage is attributed to intense food competition. Sticklebacks consume large amounts of zooplankton and benthic invertebrates, which are essential nutrients for the growth of stocked fingerlings. Additionally, they are known to prey directly on small fish larvae and serve as vectors for various parasitic infections.

Management strategies: Controlling the population of three-spined sticklebacks requires systematic intervention:

• Periodic draining and lime treatment of pond bottoms to eliminate dormant populations.
• Installation of fine-mesh screening at water inlet points to prevent the entry of individuals.
• Biological control through the introduction of predatory fish species like pike or perch.
• Targeted harvesting and population reduction programs during the spawning season.