Characterisation of Culex quinquefasciatus (Diptera: Culicidae) larval habitats at ground level and temporal fluctuations of larval abundance in Córdoba, Argentina

Abstract

The aims of this study were to characterise the ground-level larval habitats of the mosquito Culex quinquefasciatus, to determine the relationships between habitat characteristics and larval abundance and to examine seasonal larval-stage variations in Córdoba city. Every two weeks for two years, 15 larval habitats (natural and artificial water bodies, including shallow wells, drains, retention ponds, canals and ditches) were visited and sampled for larval mosquitoes. Data regarding the water depth, temperature and pH, permanence, the presence of aquatic vegetation and the density of collected mosquito larvae were recorded. Data on the average air temperatures and accumulated precipitation during the 15 days prior to each sampling date were also obtained. Cx. quinquefasciatus larvae were collected throughout the study period and were generally most abundant in the summer season. Generalised linear mixed models indicated the average air temperature and presence of dicotyledonous aquatic vegetation as variables that served as important predictors of larval densities. Additionally, permanent breeding sites supported high larval densities. In Córdoba city and possibly in other highly populated cities at the same latitude with the same environmental conditions, control programs should focus on permanent larval habitats with aquatic vegetation during the early spring, when the Cx. quinquefasciatus population begins to increase.

New records of Culicidae (Diptera) in agricultural oases of San Juan province, Argentina

“…Bionomic data. This species develops mainly in artificial breeding sites, such as ditches, sewers and pools with superficial water (Stein et al 2011(Stein et al , 2016bGrech et al 2013). Nevertheless, Almirón and Brewer (1996) reported collections in natural habitats with aquatic vegetation.…”

Mosquito (Diptera: Culicidae) larval ecology in natural habitats in the cold temperate Patagonia region of Argentina

“…Positive associations were observed between Culex species larval abundance and pH, with pH values ranging between 6.8–8.5 [10], 6.4–8.2 [60] and 7.3–11.4 [61]. However, other authors reported negative associations [62], or no relationship between this variable and immature Culex [7, 8, 11]. Conductivity and DO are two of the most useful and commonly measured water quality parameters.…”

“…In agreement, Cx. apicinus was collected less frequently from natural breeding sites including pools, spring and creek tributaries [7, 29]. In this study, Cx.…”

“…A growing body of literature indicates that one of the most important determinants for maintenance of adult populations is the presence and quality of immature breeding habitats, and may have implications for adult abundance, affecting their temporal and spatial distribution [6]. Previous studies evaluating natural and artificial habitats elucidate relationships between occurrences of species and larval habitat characteristics, identify some environmental and climatic variables that serve as drivers of vector larval abundance, identify areas with suitable habitats and evaluate the risk for disease transmission [4, 5, 7–13]. All this information is potentially useful for improving current control strategies, and should therefore contribute to more accurate predictions of the mosquito response to a changing environment [6].…”

Review of Environmental Aspects and Community Behavior in the Determination of Filariasis Risk Vulnerability Zone

“…This association occurs because the characteristics of swamps with aquatic plants can be used as breeding grounds and increase the number of mosquitoes. Culex quinquefasciatus mosquito larvae are found to be highest in permanent water habitats such as swamps with aquatic vegetation especially in summer (Grech et al, 2013).…”