Studies on the Bionomics of Aëdes aegypti (L.) in its Natural Habitats in a Coastal Region of Kenya

Studies have been made of the bionomics and ecology of Aëdes aegypti (L.) entirely under natural conditions and in its natural habitats on the Kenya coast. Development from egg to adult under conditions approximating as nearly as possible to those in nature took a minimum of eight days and a maximum of twenty-five. Males were in excess of females, in the proportion seventeen to ten, from eggs hatched in natural breeding places. Although the mosquito may be able to propagate in houses, adults from outside habitually enter premises. If this entry is for egg-laying, then eradication by domestic larval control alone, although reputedly achieved elsewhere, is not possible under conditions obtaining in the coastal belt of Kenya. Windowtrap captures, however, indicate that the entry may not be for the purpose of egg-laying. The seasonal reduction of both larvae and adults in houses during the hot, dry months of February and March is attributed to a combination of the absence of breeding places outside and the shorter life span of the mosquito at this time. It is shown that both sexes enter and leave native huts throughout the 24-hour period, but the movement is confined almost wholly to the hours of daylight. The flight from houses is much reduced in the cool months (July and August). This corresponds with the season when most enter.