SPECIES COMPOSITION, RELATIVE ABUNDANCE AND SEASONAL VARIATIONS OF MOSQUITOES BREEDING IN DIFFERENT SITES IN IKEDURU L.G.A., IMO STATE, NIGERIA

The study aimed at identifying mosquito species associated with human activities, determined species composition, relative abundance and the seasonal variations of the mosquito species in Ikeduru L.G.A., Imo State, Nigeria. Mosquitoes were randomly sampled in the area using standard methods. Results on species composition and abundance of mosquitoes confirmed eight species. They were Aedes africanus (18.84%), A. aegypti (20.16%), A. taylori (4.14%), A. albopictus (17.53%), A. luteocephalus (5.88%), Anopheles gambiae (7.79%), Culex quinquefasciatus (22.88%) and C. vittatus (2.78%) belonging to three genera (Anopheles, Aedes and Culex). Culex quinquefasciatus, Aedes aegypti, Aedes africanus and Aedes albopictus were the most abundant species encountered in this study whereas, Anopheles spp. recorded a significantly lower number. The results indicated that Aedes aegypti and A. albopictus bred well in cassava/maize processing sites; A. albopictus bred in indiscriminately dumped tires; A. africanus and C. quinquefasciatus bred well in exposed stored water while A. aegypti, A. taylori, A. luteocephalus, Anopheles gambiae and Culex vittatus bred lowly in exposed septic tank and exposed stored water. Specific analysis revealed that fermenting/ cassava processing site had a relative high abundance of mosquitoes while exposed decorated pots and vessels had the least. Three mosquito genera implicated in this study were recorded monthly throughout the year and their populations were high from April to August with peaks between June and July followed by a decline that persisted to March of the following year. Culex mosquitoes were consistently more abundant on monthly basis compared to Aedes and Anopheles. The peak population period of the mosquito genera coincided with high rainfall experienced between June and August annually in Nigeria. This has implications for effective control and therefore, time-specific interventions are necessary.