Desman

Systematic position: The desman, belonging to the genus Galemys, is part of the order Eulipotyphla and the family Talpidae. While these animals are often considered protected species in natural habitats, their burrowing activities in managed agricultural landscapes, such as fish farms and irrigation canals, can cause severe structural damage.

Nature of damage: The primary agricultural impact stems from their burrowing behavior. Desmans excavate extensive underground tunnels in embankments, levees, and pond banks. These tunnels undermine the structural integrity of water retention systems, leading to seepage, water loss, and the potential for catastrophic dam failure.

Biology and lifecycle: These are semi-aquatic mammals characterized by a nocturnal lifestyle. They build complex burrow systems with underwater entrances, which makes early detection difficult. They are prolific breeders with a high survival rate in stable aquatic environments, often leading to rapid colonization of new irrigation ditches and reservoirs.

Agricultural significance: In addition to the mechanical damage to earthworks, desmans impact aquaculture by preying on young fish and disturbing the pond bottom sediment. Their presence increases maintenance costs for hydraulic infrastructure, as constant repairs to embankments and erosion control are required to keep irrigation systems functional.

To mitigate the impact of desmans on agricultural water management, the following control strategies are recommended:

• Reinforcing canal banks with geotextiles or riprap to prevent burrowing.
• Implementing ultrasonic deterrent systems along the perimeter of critical water infrastructure.
• Conducting frequent inspections of dams to identify and fill new burrow entrances immediately.
• Using exclusion fencing to restrict access to sensitive drainage areas.
• Managing water levels to discourage nesting in high-risk zones.