The ecology of mosquito larvae (Diptera: Culicidae) in the subalpine zone of the eastern Sierra Nevada Mountains, California, U.S.A.

Abstract

Mosquito larvae were collected from the subalpine region of the eastern Sierra Nevada Mountains from 2011 to 2014. Two watersheds were sampled and sites selected were mainly vernal snow-melt pools and wet meadows. Seven Aedes species, Culiseta incidens (Thomson), and Culex tarsalis Coquillett were collected. The most abundant and widely distributed species were Ae. hexodontus Dyar and Ae. tahoensis Dyar. Aedes tahoensis was the predominate species in woodland snow-melt habitats. Some species were found at most elevations while others were found more often at specific elevations. The most restrictive species was Ae. ventrovittis Dyar which occurred almost exclusively between 3,219 m a.s.l. and 3,390 m a.s.l. Shannon and Simpson species diversity indices demonstrated that species diversity was greater in meadow habitats compared to woodland habitats. Mixed woodland/meadows, rock pools, and shallow grass pools were intermediate in species diversity. Abiotic factors such as snowpack and water temperature impacted species development times and when habitats dried. It was concluded that spatial and temporal patterns of habitats, along with elevation, influenced species presence and larval development. The results of the present study and previous work in the eastern Sierras will help guide future research that focuses on the potential change in the distribution and seasonality of subalpine mosquitoes and disease potential in the eastern Sierras as climatic conditions change.