Epi Week #31 - 2016 General Statements

The lack of rain continues to be the main story for this mosquito season, with dry habitats and little rain translating into fewer mosquitoes. Submissions were down about 17% this past week, and were about 10% lower than Epi Week 31 of 2015, but WNV+ mosquito pools saw a big jump. This jump is typical for this time of year, and also expected as drought-starved catch basins continues to provide prime Culex pipiens/restuans habitat; if you look at the table above, you’ll notice WNV+ pools are about the same as 2015, and below what they were in 2013. The predominant species varied among the mosquito control areas, with some Districts/Projects reporting abundant Coquillettidia perturbans, and other where Culex spp. were most common. While Culiseta melanura levels were up slightly from the previous week, levels of this species remained extremely low, and there is still only a single EEEv+ pool for 2016.

Weather

Drought conditions remained mostly the same across the state, with the exception of an area of “Extreme Drought (E3)” that developed at the end of Epi Week 31 into Epi Week 32.

As you can see from the Epi Week 31 map below, there was finally some rainfall this past week, with the bulk of it in the western half of the state, where some cities and towns received more than 3 inches of precipitation.