Effects of Detritus on the Mosquito : and Invasion Affect Population Performance.

Species interactions that influence the performance of the exotic mosquito can have important effects on the transmission risk of West Nile virus (WNV). Invasive plants that alter the vegetation communities of ephemeral ground pools may facilitate or resist the spread of (L.) by altering allochthonous inputs of detritus in those pools. To test this hypothesis, we combined field surveys of roadside stormwater ditches with a laboratory microcosm experiment to examine relationships between performance and water quality in systems containing detritus from invasive (Cav.) Trin. Ex Steud., introduced (Schreb.) Dumort., or native L. or L. In ditches, abundance was unrelated to detritus species but female were significantly larger from ditches with and smaller with . Larger and smaller were also produced in microcosms provisioned with and respectively, yet the per capita rate of population of change did not vary. Larger females from habitats with were likely caused by faster decay rates of and resultant increases in microbial food, but lower survival as a result of fouling and higher tannin-lignin concentrations resulted in little changes to overall population performance. Larger female mosquitoes have been shown to have greater potential for transmitting arboviruses. Our findings suggest that changed community-level interactions from plant invasions in urban ephemeral ground pools can affect the fitness of pipiens and possibly increase WNV risk.