Kentucky is home to more than 50 mosquito species with a range of breeding sites and survival strategies. | Photo: iStock

Kentucky is home to more than 50 mosquito species with a range of breeding sites and survival strategies. Some thrive when above-normal rainfall creates temporary ground pools; others develop in small accumulations of stagnant water during dry periods.

Many of our mosquito species spend the winter as freeze-resistant eggs that can survive prolonged harsh conditions. A few, such as the house mosquito (Culex pipiens), spend the winter as adults in protected places. They are vulnerable to severe cold, but like most insects have the reproductive capacity to build numbers by late summer, even if winter mortality is high.

Several mosquito species feed on horses with varied effects that range from adverse skin reactions to disease transmission. Proteins injected in mosquito saliva can produce irritating bites that can cause skin reactions in sensitive individuals. The inland floodwater mosquito (Aedes vexans) is a widespread pest that can develop in any ground pool that lasts 10 to 14 days. It causes a significant and chronic problem in some parts of the state and can give rise to several generations each year. Females rest on vegetation and shaded grass during the day and bite viciously at dusk and after dark. They can live for several weeks and travel several miles during that time. Feeding by large numbers of these mosquitoes at night can produce dermatitis and itching in horses on pasture