Anopheles gambiae (Diptera: Culicidae) oviposition as influenced by type of water infused into black and red soils of western Kenya

Abstract

The aim of this study was to document what water types were most stimulatory to oviposition by the malaria mosquito, Anopheles gambiae Giles s.s. In laboratory choice tests, dishes of black cotton and red laterite soils from around Kisumu, Kenya, equally stimulated An. gambiae oviposition when saturated with water. When infused into either soil type, water from Lake Victoria was significantly more stimulatory than any other type of water or infusion tested. Water from natural An. gambiae puddle habitats, borehole water, cow dung infusion, Bermuda grass infusion and distilled water followed in declining rank order. Relative to An. gambiae puddle-habitat water and distilled water, Lake Victoria water appears to provide the strongest chemical cues for An. gambiae oviposition recorded to date. This work suggests that this important vector of human malaria may oviposit in and around Lake Victoria, as well as in its usual puddle habitats. Lake Victoria should be explored for its possible contribution to malaria mosquito populations.