Winter migratory birds begin arriving; duck population nearly triples, prompting tighter AI controls

As winter migratory birds begin moving south into South Korea, the population of ducks and other waterfowl highly susceptible to highly pathogenic avian influenza (AI) has grown to nearly three times last year's level, authorities said.

With AI detections in wild birds overseas also more than doubling, health authorities said they will strengthen surveillance and disinfection measures ahead of the main winter migration, expected in the latter half of this month.

According to the Ministry of Climate, Environment and Energy and the Ministry of Agriculture, Food and Rural Affairs, a survey conducted Sept. 25 through Sept. 27 by the National Institute of Biological Resources at 10 major migratory bird habitats nationwide found 57,036 waterbirds, confirming that some winter migratory birds have begun arriving in the country.

Among the surveyed sites, three locations — the Han River estuary, Sihwa Lake and Sapgyo Lake — recorded 23,893 waterbirds, a 53.1 percent increase from September last year.

Over the same period, ducks and other waterfowl with high susceptibility to highly pathogenic AI numbered 18,678, a 189.7 percent increase — roughly 2.9 times the year-earlier figure.

According to the World Organisation for Animal Health, the number of highly pathogenic AI detections in wild birds abroad also more than doubled, rising from 1,432 cases in January through August last year to 2,957 cases in the same period this year.

The Ministry of Climate, Environment and Energy has expanded its migratory bird surveillance points from 102 to 112 and is intensively monitoring 22 sites identified as early stopover locations or high-risk areas for AI outbreaks.

The ministry also plans to work with Mongolia, Japan and other countries to analyze migratory routes and behavioral patterns using tracking devices, and to rapidly assess the risk and spread of the virus based on the genotypes detected domestically.

The Ministry of Agriculture, Food and Rural Affairs issued a high-risk AI alert to livestock farms nationwide on Wednesday and has been disinfecting roads near migratory bird habitats and farm access routes. It has also designated 280 restricted zones for livestock vehicle access.

If highly pathogenic AI is detected in wild birds, authorities plan to designate a 10-kilometer radius around the detection site as a surveillance zone, restrict the movement of people and vehicles for 21 days, and conduct inspections and intensive disinfection at nearby poultry farms.