Leveraging the mosquito holobiont to suppress disease and advance avian conservation

This research focuses on Hawaiian honeycreepers, a diverse group of birds. Honeycreepers are important in sustaining Hawaiian ecosystems and the cultural identity of indigenous Hawaiians. However, over half of the species have gone extinct, and most of the remaining species face imminent extinction. The driver of this extinction crisis is an introduced avian malaria parasite transmitted by an invasive mosquito species. Government and community partners are working together to suppress mosquitoes and prevent avian malaria transmission. Mosquitoes are being suppressed by releasing sterile males into the environment. These males are sterile because they have a bacterium that lives inside their cells. When male mosquitoes with these bacteria are released, they mate with wild females and decrease their reproduction. However, ecological knowledge gaps may limit the plan’s efficacy. This project will fill these gaps by determining where to release of these male mosquitoes on the landscape and how to increase their mating success following release. This project has broad implications for the management of mosquito-borne diseases, including those that affect human health. In addition, this project will engage in workforce development with native Hawaiians to help restore natural resource management agency to this indigenous group. The central hypothesis of this research is that microorganisms underlie the response of macroorganisms to a changing environment. This hypothesis is tested using mosquito populations of the avian malaria vector, Culex quinquefasciatus, across gradients in temperature and humidity that vary dramatically with elevation in Hawaii. The first aim clarifies the landscape-scale Cx. quinquefasciatus population dynamics by using metagenomic data to infer whether the mosquito holobiont covaries with elevation in a Hawaiian forest, a pattern consistent with local adaptation or acclimation of the holobiont to environmental regimes. In addition, genomic data and stable isotope tracking will be employed to resolve the connectivity of Cx. quinquefasciatus populations across this mountainous landscape to understand mosquito dispersal and its ramifications for the spread of microbial symbionts, including avian malaria parasites. The second aim manipulates the microbiome component of Cx. quinquefasciatus to understand its impact on adult mosquito phenotypes that influence the performance of the mosquito in its environment. Through controlled laboratory, microbiome transplantation, and common garden experiments, this work will clarify how the mosquito microbiome influences mosquito fitness in cool, high elevation environments where they currently cooccur with native Hawaiian honeycreepers. The third aim monitors the implementation of incompatible insect technique on Kauai, Hawaii to suppress Cx. quinquefasciatus populations in Hawaiian honeycreeper habitat. This effort will document the efficacy of this technique and inform mathematical models that will be used to hone future incompatible insect technique implementation in Hawaii and beyond. This project is jointly funded by the Divisions of Environmental Biology and Integrative Organismal Systems through the Partnership to Advance Conservation Science and Practice Program. This award reflects NSF’s statutory mission and has been deemed worthy of support through evaluation using the Foundation’s intellectual merit and broader impacts review criteria.

Project details

Climate Change

Nov 2024 — Oct 2027

$651,084

United States