The effects of high-altitude windborne migration on survival, oviposition and blood-feeding of the African malaria mosquito, Anopheles gambiae s.l

Recent results of high-altitude windborne mosquito migration raised questions about the viability of these mosquitoes despite ample evidence that many insect species, including other dipterans have been known to migrate regularly over tens or hundreds of kilometers on high-altitude winds and retain their viability. To address these concerns, we subjected wild s.l. mosquitoes to a high-altitude survival assay, followed by oviposition (egg laying) and blood feeding assays. Despite carrying out the survival assay under exceptionally harsh conditions that probably provide the lowest survival potential following high altitude flight, a high proportion of the mosquitoes survived for six and even eleven hours assay durations at 120-250m altitudes. Minimal differences in egg laying success were noted between mosquitoes exposed to high altitude survival assay and those kept near the ground. Similarly, minimal differences were found in the female’s ability to take an additional blood meal after oviposition between these groups. We conclude that similar to other high-altitude migrating insects, mosquitoes are able to withstand extended high-altitude flight and subsequently reproduce and transmit pathogens by blood feeding on new hosts.