Eg., I expect that many people's intuition would tell them the same as mine - drought will decrease mosquitos, abundant rain will increase them. But not so.
I live in the Atlanta, Georgia metro area. A few years ago, one month in the spring it rained almost every day. At first I expected that would result in a heavy mosquito population. But the scientists foretold that we would have a lighter than usual mosquito problem, because the heavy rains would wash away the mosquitos, and that's what happened. And not just to mosquitos. I control fleas on my cats with a flea comb. With the combination of heavy rains one month washing away fleas and their eggs, followed by (?four) months of almost no rain, there was a period of more than a year where I did not find a single flea on any of my four cats! Unfortunately, the flea population seems to be back to normal.
Atlanta has been experiencing drought since last year. One would hope that it would have at least a positive side effect of fewer mosquitos. But alas, no.
http://www.ajc.com/search/content/metro/stories/2007/09/19/westnile0919.html
into next month, public health experts said Tuesday.
Experts said the persistently dry weather, favored by these bugs that breed in stagnant water, may extend an already active peak season of West Nile.
"It may drag on a little bit into the fall, because there have not been significant rains," said Elmer Gray, a University of Georgia Extension Service public health specialist.
Heavy rains, he said, flush out the stagnant water in storm drains, ponds and bird baths.
The peak transmission period typically lasts from mid-August to mid-September, but Gray said he expects the peak to continue until as late as mid-October.