Type C botulism was determined to be the cause of an epizootic among waterfowl and shorebirds in a phosphate mine settling pond in northern Florida during May and June of 1979. Several hundred birds, the most common of which were American coots (Fulica americana), wood ducks (Aix sponsa), common gallinules (Gallinula chloropus), and northern shovelers (Anas clypeata) were afflicted over about a three-week period. A second smaller outbreak occurred in the same pond in early December of 1979. This is apparently the first time that botulism has been reported in waterbirds of Florida.