Invasive Species Compendium

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Abstract

Original article study of oviposition behavior of Aedes aegypti in two neighborhoods under the influence of semi-arid climate in the municipality of Salinas, state of Minas Gerais, Brazil.

Abstract

The mosquito Aedes aegypti (Diptera: Culicidae) is the main vector of human arborvirus in Brazil. Oviposition behavior is important for the survival and dispersal of A. aegypti. The objective of this study was to evaluate the oviposition behavior and its relationship to meteorological factors. Twenty ovitraps were installed in two neighborhoods in the urban area of the city of Salinas, MG, southeastern Brazil. The traps were inspected weekly for the presence of eggs in the water and on the paddle. Simultaneously, regional weather data were analyzed. The results showed the Ovitrap Positivity Index (OPI) varied greatly, from 0 to 90%, between the weeks and boroughs sampled, demonstrating the vector's great population fluctuation. Among the analyzed climatic factors, rainfall strongly influenced oviposition, followed by relative air humidity. The number of eggs found on the paddle was significantly higher than in the water (p<0.05). However, a significant increase of eggs in the water was noticed when the relative humidity dropped below 40%. This seems to be an important behavior to maintain the population in periods of drought. Through the low number of eggs (<30) found in 56% of positive traps, we concluded that skip-oviposition behavior occurred, contributing to the prevalence of mosquitoes during the sampled period. It is concluded that the occurrence of water oviposition may be higher than described in the literature, and should be studied due to its evolutionary and epidemiological importance.