HR: 1330h
AN: NB33T-09    [Abstracts]
TI: Habitat Variation in Wetland Invertebrate Communities With Varying Mosquito Larviciding Strategies
AU: * Marcus, M A
EM: mamarcus@uwo.ca
AF: Department of Biology, The University of Western Ontario, London, ON N6B 5B7 Canada
AU: Bailey, R C
EM: drbob@uwo.ca
AF: Department of Biology, The University of Western Ontario, London, ON N6B 5B7 Canada
AB: Monitoring, surveillance, and vector control of West Nile virus have received much attention and public resources in North America following the occurrence of human cases in 1999. With increased frequency of mosquito prevention and control programs, investigation of long-term ecological effects of larvicides used on wetland invertebrate communities is necessary. Before these effects can be examined, the variation among ponds and wetlands in features other than larviciding history needs to be examined. In a study on Bacillus thuringienisis israelensis (Bti), in the Township of East Gwillimbury and surrounding area, located in Southern Ontario, Canada, 18 wetlands were repeatedly sampled over a 5 month period. Physical habitat features, water chemistry (i.e. temperature, pH, conductivity, and dissolved oxygen), and metal and ion concentrations were measured and Principal Component Analysis was used to determine how ecosystem descriptors varied and covaried among ponds. Results showed sites with high sodium and chloride concentrations were positively correlated with both submerged and herbaceous plants in sandy environments and relatively high pHs. Based on these results, we predict weak effects of larvicide treatment on pond invertebrate communities relative to other natural and anthropogenic factors.
DE: 9810 New fields (not classifiable under other headings)
DE: 9902 NABS Student Award Applied Research
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly