A northern shoveler duck (Anus clypeata) killed by botulism in Farmington Bay of the Great Salt Lake. Outbreaks of botulism are common in eutrophic waters such as occur in Farmington Bay which has massive cyanobacteria (Nodularia) blooms when salinities range from 10-50 ppt. One hypothesis is that cyanotoxins produced by cyanobacteria (blue-green algae) weaken and kill waterfowl, which are then infested with the botulism bacteria. 10,000 shovelers died in Farmington Bay during the summer die-off of 2006.


Photo: 16 July 2006. Sonja Raub