Estudi de la dinàmica poblacional de les poblacions de culícids als arrossars del Baix Empordà

Abstract

Due to the growing interest in the ecology of mosquitoes and their population dynamics, we conducted a study on the culicid species present in the Baix Empordà rice fields, assessing the temporal variations of their adult populations. We also evaluate the possible influence of different environmental variables and soil cover in a radius of 100, 300 and 500 meters from each sampling point, to include the flight distance of the detected species. Since the importance of meteorological factors such as temperature, wind intensity and precipitation has been described in previous studies, we incorporate data retrieved on the Estartit’s meteorological station. The sample gathering was done by means of 6 Biogents Mosquitaire traps (suction traps) and 15 stations distributed throughout the study area. A total of 3988 mosquitoes are determined, belonging to seven different species. 99.7% of the trapped individuals are included in the Culex genus. Within this genus, contrary to what might be expected at first, C. modestus dominates over C. pipiens, and C. theileri presents very low population densities. No individuals of the genus Aedes are detected, and Culiseta and Anopheles appear anecdotally. Among the meteorological variables considered in this study, we find significant results in the cases of minimum temperature, wind intensity and relative humidity, always showing negative correlations with the number of catches. It is important to note that the used variables were collected in a meteorological station located 9 km away from the study area, and therefore the results may stray from the reality in a certain measure. In agreement with the expected results, spatial heterogeneity manifests a negative relation with the number of detected adults, and the forested areas favor the mosquitoes’ presence