Breeding Habitat Preferences of Mosquitoes and Associated Physicochemical Conditions in Oraifite, Nigeria

Abstract

Aims: This study assessed mosquito larval breeding habitats and examined the relationship between selected physicochemical parameters and larval abundance in Oraifite, Ekwusigo Local Government Area, Anambra State, Nigeria. Study Design: A longitudinal field survey was conducted across wet and dry seasons. Place and Duration of Study: The study was conducted in eight communities in Oraifite, Nigeria, over 12 months. Materials and Methods: Mosquito larvae and pupae were collected from man-made containers, ground pools, and plant axils. Immature stages were reared to adults and identified using standard taxonomic keys. Physicochemical parameters of breeding water, including pH, salinity, total suspended solids, total dissolved solids, dissolved oxygen, sulphate, surface water temperature, and turbidity, were measured using standard procedures. Larval abundance was summarised by species, breeding-site type, community, and season, while relationships between physicochemical parameters and larval abundance were examined statistically. Results: A total of 1,156 mosquito larvae were collected. Seven species were identified: Aedes aegypti, Aedes albopictus, Aedes simpsoni, Anopheles gambiae, Culex quinquefasciatus, Culex tigripes, and Ae. luteocephalus. Man-made containers yielded the highest larval abundance, whereas plant axils yielded the lowest. Aedes aegypti was the most abundant species, followed closely by Aedes albopictus. Larval abundance was highest during the late wet season, particularly in August and September. Physicochemical conditions varied by breeding-site type, and pH, sulphate, and surface water temperature appeared to influence larval occurrence in some habitats. However, the statistical associations should be interpreted cautiously because some regression models were not significant. Conclusion: Mosquito larvae in Oraifite occurred in diverse artificial and natural breeding sites, with late wet-season peaks. Targeted source reduction, regular surveillance, and management of container habitats and ground pools are recommended.