A stable isotope mark-capture study of Culex quinquefasciatus and Aedes albopictus in College Station, Texas

To better control populations of mosquitoes and break the transmission cycle of vector-borne diseases, it is crucial to understand the dispersal of adult mosquitoes. We performed a stable isotope mark-capture study, focusing on Culex quinquefasciatus and Aedes albopictus, to characterize dispersal distance and behavior. We enriched (i.e. marked) naturally occurring larval mosquitoes in container habitats with ¹³C-glucose or ¹⁵N-potassium nitrate at two different locations (~0.05km apart) in College Station, Texas in 2013. We used 32 CDC light trap, 32 gravid trap, and 16 BG Sentinel trap locations within a two-kilometer radius of the enriched larval habitats.  Each location was trapped once per week and all mosquitoes collected were identified and numerated. Cx. quinquefasciatus and Ae. albopictus were pooled and tested for West Nile virus by RT-PCR or tested by stable isotope analysis.  In total 720 trap nights were completed from July to August 2013 yielding a total of 32,140 Cx. quinquefasciatus and 7722 Ae. albopictus. Although stable isotope results for enriched female mosquitoes are still pending, of the 1832 pools tested, sixteen were enriched with ¹³C and twelve were enriched with ¹⁵N. The mean dispersal distances of Cx. quinquefasciatus and Ae. albopictus from ¹³C are 792.1m and 375.2m, respectively. The mean dispersal distances of Cx. quinquefasciatus and Ae. albopictus from ¹⁵N are 400.2m and 250m, respectively. This study provides a greater understanding of the dispersal of two important mosquito vectors capable of transmitting diseases in urban environments. We also confirm the ability to use stable isotope enrichment as a means to study the biology of mosquitoes.