The larvae and pupae of mosquitoes found in a flooded dambo on a bushed grassland in Central Province, Kenya were monitored during the short rainy season. The densities of the immature stages of 8 species were recorded daily for a one month period. Aedes cumminsii mediopunctatus, Ae. lineatopennis and Ae. sudanensis were collected for 8, 9 and 18 days respectively and each disappeared after one generation. Aedes lineatopennis and the Culex spp. specimens were collected in much greater densities than in a forest dambo studied previously.