Flooding and Mosquitoes


Now that the flood waters are receding, mosquitoes are likely to follow. Flooding per se, does not lead to mosquitoes. It is the water that stands AFTER the flooding that creates opportunities for mosquitoes to breed. Mosquito larvae require standing, stagnant water in which to feed and grow (mosquito larvae do not live in running water). It takes 7 to 10 days of standing water for the mosquitoes to develop, which is why we see mosquitoes after the flood rather than during. With receding flood waters and drier conditions the mosquito problem will increase in many areas across Iowa over the next few weeks.

Personal protection with a repellant that contains DEET is the best choice if you have to be outside during peak mosquito activity hours (usually dusk, although mosquitoes can be active all day). Female Aedes vexans, a floodwater mosquito, usually rest during the day and seek out blood meals at dusk. This species can become prevalent after flooding, but is a species that has minimal involvement in the transmission of West Nile Virus.


Please see Ken Holscher's article about mosquito management in the June 18, 2004 HHPN


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