Species Abundance, Composition And Colonization Behaviour Of Malaria Vectors In A Semi-arid Ecosystem Of Baringo District, Kenya.

Malaria is one of the public health problems facing people in many parts of Kenya including semi-arid areas. It is caused by an infectious bite of female Anopheles mosquitoes. To effectively implement malaria control program, the knowledge of colonization, resting behavior of the vectors and effect of distance between houses and breeding habitats on mosquito abundance is required. This research set out to determine seasonal dynamics, outdoor resting habits and colonization of larval habitats by Anopheles vectors of malaria. The study was conducted in Kamarimar village in Baringo District adjacent to Loboi swamp. Larval survey was conducted once weekly by making 10-20 dips per habitat using standard dipper (350 ml). Ten houses were sampled by use of Pyrethrum Spray Catches (PSC) once a week for adult mosquitoes and aspiration method once a fortnight. Data was analyzed using SAS version 9.2. Mosquito breeding habitats comprised pan dams, ditches, marshes and canals. Marshes were relatively productive larval habitats and produced 35 out of the total 74 larvae collected in the dry season. However, no larvae were collected from canals. Pan dams, ditches and culverts produced 28, 9 and 2 Anopheles larvae respectively. Out of 281 Anopheles larvae collected from all the breeding habitats, 207 were collected during the rainy season. An. gambiae was found to breed in pan dams and ditches in both seasons and were constantly available during the rainy season in which 91 larvae were collected while the dry season realized only 22 larvae. An. funestus larvae were few but during the dry season, 21 larvae were collected from the swamp marshes and pan dams while in the rainy season, only 9 larvae were collected.