Ecological Factors Favouring Mosquito Breeding in Akure South Metropolis, Ondo State

Mosquitoes are major vectors of many infectious diseases, and they strongly relate their abundance to the ecological attributes of their breeding sites. With a focus on the physico-chemical and physical characteristics of larval habitats and their correlation with larval density, abundance, and species distribution, this study examined the ecological factors that favour mosquito breeding in Akure South Metropolis, Ondo State, Nigeria. Field sampling was done across selected wards where mosquito larvae could be collected from identified breeding sites using standard dipping techniques, reared to adulthood, and identified morphologically. Water temperature, pH, dissolved oxygen, electrical conductivity, total dissolved solids, habitat length, breadth, depth, and distance to the nearest building were measured on-site. A total of 4,001 adult mosquitoes belonging to four genera (Culex, Aedes, Anopheles, and Toxorhynchites) were recorded, with Culex species being the most abundant and widely distributed Isikan showed the highest mosquito distribution, larval abundance, and dissolved oxygen, whereas Odopetu showed the highest electrical conductivity and total dissolved solids, reflective of higher ionic and organic enrichment. Correlation analysis revealed that larval density was positively associated with pH and dissolved oxygen, indicating preference for moderately acidic to near-neutral and well-oxygenated waters, but negatively correlated with temperature, total dissolved solids, and electrical conductivity, suggesting that excessive heat and chemical enrichment may limit larval survival. Physical habitat characteristics further influenced larval distribution, as larval density was positively correlated with habitat length and proximity to buildings, but negatively correlated with habitat breadth and depth, demonstrating that shallow, narrow, elongated water bodies close to human dwellings are more favourable for mosquito breeding than wider and deeper habitats. The study shows that mosquito breeding in Akure South Metropolis is strongly driven by an interaction of water quality, habitat structure, and anthropogenic activities, highlighting the need for improved environmental sanitation, drainage management, and targeted larval source reduction to effectively control mosquito populations and reduce the risk of mosquito-borne diseases.