Possible biotic interactions that are affecting the presence and abundance of Aedes albopictus (Diptera: Culicidae) in Misiones, Argentina

A. A. LIZUAIN; M. LEPORACE; L. MAFFEY; M.J. GARZÓN; N. J. SCHWEIGMANN; M. S. SANTINI

La Plata

Congreso; II Congress of the Latin American Society for Vector Ecology; 2022

In Argentina, despite local Aedes albopictus presents a latency that would allow to be present at temperate latitudes its distribution is limited to two provinces with a subtropical climate: Misiones and Corrientes. It is possible that there are other factors are limiting the expansion of this vector. To evaluate possible interactions that are affecting population and spread of this specie, we sampled artificial breeding site of Eldorado (urban environment) and Colonia Aurora (rural environment), Misiones province, in October of 2015, April and November of 2016 and April of 2017. We performed generalized linear mixed models to evaluate which variables (type of container, volume of water, municipality, and zone -urban, suburban, rural) are associated with the presence and abundance of Ae. albopictus and Ae. aegypti, and the presence of mosquito predators (Lutzia bigoti and Toxorhynchites spp.). Also, in each municipality, relationship between Ae. albopictus and Ae. aegypti was quantified through Hurlbert´s C8 association coefficient. A total of 22514 larvae of eleven mosquito taxa were collected in 407 breeding site. Aedes aegypti was the most abundant species with 53.82% of specimens, followed by Cx. quinquefasciatus (23.65%), Ae. albopictus (10.58%) and Ae. fluviatilis (6.90%). Presence of the Asian tiger mosquito were higth in Colonia Aurora (χ2= 4.933; df=1; p= 0.026) and in conteiners with 1-100 liters of water (χ2= 19.228; df=3, p=2; 453e-4). Presense and abundance of Ae. aegypti were was high in Eldorado (χ2= 36.196; df=1; p=1.784e-09 / χ2= 32.513; df=1; p= 1.184e-08). And also, in abundances was elevated in the containers with less and greater volumes of water (χ2=14.234; df=3; p=0.003) (0-1l and >100l). The presence of predators was explained by type of containers (χ2= 7.159; df=2; p=0.028) and municipality (χ2= 4.048; df=1; p=0.044). Tires and containers of Colonia Aurora had a highest presence of predators (representing 29.03% of the breeding sites in that municipality in November 2016). Regarding C8 index, Ae. aegypti was negatively associated with Ae. albopictus in Eldorado city (C8=-0.105) and; in the rural municipality of Colonia Aurora, these species presented a significantly positive relationship (C8=0.376). These results show that in urban environments the high abundance of Ae. aegypti could be affecting the Asian tiger mosquito as evidenced by local studies of food larval competition. Also a greater presence of predators could be affecting Ae. albopictus in tires and rural environments.