Greater Scaup

The Greater Scaup (Aythya marila) belongs to the order Anseriformes, family Anatidae. While essentially a wild waterfowl species, in specific agricultural landscapes, it is recognized as a potential pest of semi-aquatic crops, with rice paddies being particularly susceptible to their foraging activities.

The primary agricultural impact occurs during the sowing and early growth stages of rice. The birds forage in flooded paddies, consuming large quantities of sown seeds and uprooting young seedlings. This feeding behavior often leads to significant stand thinning and necessitates costly reseeding operations.

The biology of the Greater Scaup is fundamentally tied to large water bodies. During migration and the molting season, large flocks frequently concentrate on artificial ponds and irrigation systems. When these sites are adjacent to farmland, the birds opportunistically utilize agricultural fields as vital feeding grounds.

The damage caused by the Greater Scaup is both direct and indirect. Direct damage involves the consumption of crop biomass, while indirect damage includes the trampling of mud and the disturbance of the soil-water balance within the paddy. These activities hinder the optimal establishment of the crop cycle.

Effective management strategies for protecting crops against the Greater Scaup include:

• deploying propane cannons and acoustic deterrent devices
• utilizing motion-activated light systems and lasers
• placing realistic predator decoys across the fields
• adjusting water management schedules during peak migration periods