Factors affecting mosquito populations in created wetlands in urban landscapes: Fid-Bau Portal

Factors affecting mosquito populations in created wetlands in urban landscapes

Yadav, Priyanka / Foster, Woodbridge A. / Mitsch, William J. / Grewal, Parwinder S.

Abstract Constructed, created and restored wetlands are gaining popularity in urban areas due to many ecosystem services they provide. However, there is a concern over mosquito breeding in such wetlands. We studied factors affecting mosquito populations in two experimental flow-through created wetlands, a stormwater wetland, a pond and 40 mono-specific and mixed plant mesocosms (1 $ m^{2} $) at the Olentangy River Wetland Research Park (ORWRP) in Columbus, Ohio. The flow-through created wetlands had less mosquito larval density (2 to 4/dip) compared to the pond (36.2 ± 8.4/dip) (p < 0.00001) and stormwater wetland (24.9 ± 10.2/dip) (p = 0.002). Sites with higher larval density in the flow-through wetlands were outflow regions (p = 0.009) and emergent vegetation sites (p = 0.023). Mixed vegetation communities consisting of Sparganium eurycarpum, Juncus effusus, and Schoenoplectus tabernaemontani rather than mono specific Typha communities provided most conducive environment for mosquito breeding (p < 0.0001). Mesocosm plots with steady inflow (10 cm depth) and deep water (20 cm) in summer and shallow water (5 cm) in spring had higher mosquito densities than mesocosm plots with other hydrological conditions. Among water quality parameters, conductivity (p = 0.004) positively and dissolved oxygen (p = 0.052) negatively correlated with mosquito larval density. Six mosquito species identified in all water bodies were Culex pipiens, Culex salinarius, Culex restuans, Uranotaenia sapphirina, Anopheles quadrimaculatus, and Anopheles punctipennis some of which may transmit deadly human pathogens. This information will be useful for targeting mosquito populations in specific sections of urban created wetlands and to develop improved designs for urban wetlands.