The characterization of microbiota changes pre/post larval mosquito treatment in post-Hurricane Sandy tree divot habitat

Natural disasters such as hurricanes and other major storm events can provide the conditions for increases in suitable mosquito habitat and resulting mosquito populations. Mosquito control in these ephemeral habitats often includes bactericides (eg Bti) or insect growth inhibitors (eg methoprene) that could affect the mosquito internal microbiome. The objectives of this study were to characterize hurricane-created tree divot habitat and mosquito and microbial diversity within these ephemeral habitats, pre/post mosquito control treatments. This study was conducted in Hunterdon County, NJ. Physical/chemical data were collected from 21 tree divots and mosquito larvae were collected pre/post Bti and methoprene application. Subsurface water was collected with a 60 cc syringe and filtered onto a 0.2 micron membrane. Surface microlayer samples were collected using a glass plate method and filtered similarly. Bacteria and Archaea communities of the water and inside mosquito larvae were characterized using 16sRNA amplicon metagenomic sequencing. We found Aedes stimulans as the only Culicidae in all divots. Treatment with BTI caused the greatest reduction in larval density. The divots showed an increase in pH as temperature increased and volume decreased, regardless of treatment. The microbial community structure of the water and the internal microbiomes of the mosquito larvae varied between divots and treatment, suggesting potential effects of control methods on habitat and insect microbial ecology that may provide new information on additional control targets in larval mosquitoes.