(Montana State University - Bozeman, College of Agriculture, 2007) Doherty, Melissa Kuckler; Chairperson, Graduate Committee: Greg Johnson.
Coal bed natural gas development in northeastern Wyoming has increased surface water in ranching and agricultural areas over undeveloped land. This increase of water increases larval habitat for mosquitoes, potentially increasing adult populations of West Nile virus vector mosquitoes. I compared adult and larval mosquito populations in four different habitat types in the Powder River basin including agricultural, natural, CBNG and upland sagebrush steppe. Adult mosquitoes were sampled weekly (2004) or bi-weekly (2005) using CDC miniature black-light traps baited with dry ice. A fixed-effect mixed model indicated that in a normal rainfall year (2005) mature CBNG ponds had the highest adult mosquito populations of all sites sampled, and the highest population of the WNV vector Culex tarsalis. In a drought year (2004) where total rainfall from May - August was 59% of the seasonal average, agricultural areas had the highest mosquito abundance, likely due to increased irrigation. Adult Culex tarsalis tested positive for WNV across the PRB in 2004 and 2005, with highest minimum infection rates in those areas with large Culex tarsalis populations.
