An outbreak of botulism occurred over a two-month period beginning July 20, 2016. In all, 697 wild birds were found paralyzed or dead at the Namdong reservoir and 11 Gong-gu. Using a mouse bioassay, type C botulinum toxin was identified in the bird serum, liquid cultures of soil samples, and maggot extracts. To minimize further infection of wild birds, we opened the floodgates of the Namdong reservoir adjacent to the Yellow Sea; this decreased the water temperature and the nutrient load such as nitrogen and phosphorus. The outbreak stopped shortly after taking these actions. It is not known if these efforts decreased the number of dead and diseased wild birds. Our study demonstrates one potential approach to minimize future botulism outbreaks among wild birds and their habitats.
Keywords: avian botulism; type C botulism; wild bird.