Mosquito Sugar Feeding and Survivorship on Endemic Flowers of Arid Scrubland

Mosquitoes, like many other insects, are dependent on sugar sources. Mosquito-plant interactions in high elevation deserts, such as in the intermountain west of the United States, are understudied. In the state of Utah, where salt desert shrublands meet alkaline wetlands, plant communities contain a diversity of native and invasive flower species. We investigated survivorship on flowering plants using local Culex pipiens (L.) under laboratory conditions. Four native angiosperm species, Cleome serrulata Pursh (Brassicales: Cleomaceae), Asclepias incarnata L. (Gentianales: Apocynaceae), Asclepias speciosa Torrey, and Verbena hastata L. (Lamiales:Verbenaceae) had the highest mosquito mean percent survival in 10-day assays. Mosquito survival was significantly better on native flowers than on non-native flowers. Endemic mosquitoes in the field were also sampled for frequency of sugar-feeding at six sites across 11 weeks. Flower phenology data of the aforementioned four flowers with highest mosquito mean percent survival was taken from iNaturalist and compared to the abundance of sugar-fed mosquitoes from the wild. Generally, flower phenology and sugar-fed mosquito abundance followed the same trends, with increased flower sightings co-occurring with increased sugar feeding. Utah, which has comparable habitat to other arid areas, experiences time periods when both flower sightings and sugar feeding in mosquitoes is low, highlighting elevated risks to exposure and malnutrition for wild populations. Sustainable research and management of mosquitoes requires answers to basic biological and ecological questions such as flower dependence and resource scarcity in the field.