CAN BOTULISM EPIDEMICS BE PREVENTED? 



Three factors contributing to the development of epidemics are: lowered water levels dur- 

 ing hot summer months, an abundance of flies, and animal carcasses for toxin production. 

 Disease prevention efforts, therefore, should focus on these factors. 



Control of Water Levels 



Areas managed for shorebirds and waterfowl should not be reflooded in summer if the 

 areas have been dry for a prolonged period of time. Rather, reflooding to accommodate the 

 fall migration should take place when temperatures become cooler in early fall. Similarly, 

 summer drawdowns of impounded water should be avoided because that can result in fish 

 kills. Fish carcasses also provide a suitable medium for bacterial growth. Some management 

 programs require water drawdowns; for example, to provide a feather edge of habitat for 

 foraging shorebirds. In these cases, botulism prevention programs must focus on stabilizing 

 water levels to maintain a minimally fluctuating feather edge. 



Carcass Removal 



Prompt removal of any carcasses that may occur is essential for preventing development 

 of die-offs during periods with hot daytime and warm nighttime ambient temperatures. For 

 example, when control of undesirable fish species such as carp occurs on areas used by 

 birds, managers need to dispose properly of fish carcasses. All animal carcasses should be 

 removed and burned or buried deeply. This will eliminate the major source of toxin produc- 

 tion and maggot development. If these steps are not taken, toxin materials may build up 



