Environmental Characteristics Associated with the Occurrence of Avian Botulism in Wetlands of a Northern California Refuge
Rocke TE, Euliss NH, Samuel MD. 1999. Environmental Characteristics Associated with the Occurrence of Avian Botulism in Wetlands of a Northern California Refuge. The Journal of Wildlife Management. 63(1):358-368
Avian botulism is an important disease affecting many species of waterbirds in North America, but the environmental conditions that initiate outbreaks are poorly understood. To determine wetland attributes associated with outbreaks of avian botulism in waterbirds at the Sacramento Wildlife Refuge, we compared environmental characteristics between wetlands where outbreaks occured in sentinel mallards and where they did not occur. Multivariate analysis was used to reduce 22 environmental variables to 7 factors for inclusion in subsequent statistical analyses. We found that outbreak wetlands had significantly lower redox potential than nonoutbreak wetlands. The probability of botulism breakouts was associated with increased temperature, increased invertebrate abundance/ biomass, and decreasing turbidity. Because these factors were not consistently higher in outbreak wetlands than nonoutbreak wetlands, they may have a more proximate effect in initiating an outbreak.
- Type
- Journal Article
- Authors
- Rocke, Tonie; Euliss, Ned; Samuel, Michael
- Units
- KAHO
- Keywords
- Anas platyrhynchos, Avian Botulism, botulinum toxin, Clostridium botulinum type C, environmental characteristics, sentinel mallards, Water Quality, Waterfowl, Wetlands